ORCID Profile
0000-0002-0008-9733
Current Organisation
Telethon Kids Institute
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Cardiorespiratory Medicine and Haematology | Public Health and Health Services | Environmental Technologies | Infectious Diseases | Environmental and Occupational Health and Safety | Allergy | Respiratory Diseases |
ANZSRC Socio-Economic Objective (SEO)
Biofuel (Biomass) Energy | Urban and Industrial Air Quality | Respiratory System and Diseases (incl. Asthma) | Immune System and Allergy | Environmental Health | Infectious Diseases
Related Links
Publications
SELECTION OF HOUSEKEEPING GENES FOR REAL-TIME QUANTITATIVE PCR IN NORMAL AND ATOPIC HUMAN BRONCHIAL EPITHELIAL CELLS
Publisher: Elsevier BV
Date: 10-2007
SLC6A14 impacts cystic fibrosis lung disease severity via mTOR and epithelial repair modulation
Publisher: Research Square Platform LLC
Date: 09-08-2021
DOI: 10.21203/RS.3.RS-591564/V2
Abstract: Cystic fibrosis (CF), due to variants in CFTR gene, is associated with chronic infection/inflammation responsible for airway epithelium alteration and lung function decline. Modifier genes induce phenotype variability between people with CF (pwCF) carrying the same CFTR variants. Among these, the gene encoding for the amino acid transporter SLC6A14 has been associated with lung disease severity and age of primary airway infection by the bacteria Pseudomonas aeruginosa . In this study, we investigated whether the single nucleotide polymorphism (SNP) rs3788766, located within SLC6A14 promoter, is associated with lung disease severity in a large French cohort of pwCF. We also studied the consequences of this SNP on SLC6A14 promoter activity using a luciferase reporter and the role of SLC6A14 in mammalian target of rapamycin (mTOR) signaling pathway and airway epithelial repair. We confirm that SLC6A14 SNP rs3788766 is associated with lung disease severity in pwCF (p=0.020 n=3,257, pancreatic insufficient, aged 6 to 40 years old), with the minor allele G being deleterious. In bronchial epithelial cell lines deficient for CFTR , SLC6A14 promoter activity is reduced in the presence of the rs3788766 G allele. SLC6A14 inhibition with a specific pharmacological blocker reduced 3 H-arginine transport, mTOR phosphorylation and bronchial epithelial repair rates in wound healing assays. To conclude, our study highlights that SLC6A14 genotype might affect lung disease severity of people with cystic fibrosis via mTOR and epithelial repair mechanisms modulation in the lung.
Innate inflammatory responses of pediatric cystic fibrosis airway epithelial cells: Effects of nonviral and viral stimulation
Publisher: American Thoracic Society
Date: 06-2011
ACE2 Expression is elevated in Airway Epithelial Cells from aged and male donors but reduced in asthma
Publisher: Cold Spring Harbor Laboratory
Date: 29-07-2020
DOI: 10.1101/2020.07.26.20162248
Abstract: COVID-19 is complicated by acute lung injury, and death in some in iduals. It is caused by SARS-CoV-2 that requires the ACE2 receptor and serine proteases to enter airway epithelial cells (AECs). To determine what factors are associated with ACE2 expression particularly in patients with asthma and chronic obstructive pulmonary disease (COPD). We obtained upper and lower AECs from 145 people from two independent cohorts, aged 2-89, Newcastle (n=115), and from Perth (n= 30) Australia. The Newcastle cohort was enriched with people with asthma (n=37) and COPD (n=38). Gene expression for ACE2 and other genes potentially associated with SARS-CoV-2 cell entry were assessed by quantitative PCR, protein expression was confirmed with immunohistochemistry on endobronchial biopsies and cultured AECs. Increased gene expression of ACE2 was associated with older age (p=0.02) and male sex (p=0.03), but not pack-years smoked. When we compared gene expression between adults with asthma, COPD and healthy controls, mean ACE2 expression was lower in asthma (p=0.01). Gene expression of furin, a protease that facilitates viral endocytosis, was also lower in asthma (p=0.02), while ADAM-17, a disintegrin that cleaves ACE2 from the surface was increased (p=0.02). ACE2 protein levels were lower in endobronchial biopsies from asthma patients. Increased ACE2 expression occurs in older people and males. Asthma patients have reduced expression. Altered ACE2 expression in the lower airway may be an important factor in virus tropism and may in part explain susceptibility factors and why asthma patients are not over-represented in those with COVID-19 complications. ACE2 is the primary receptor for SARS-COV-2. We demonstrate that lower airway expression of ACE2 is increased in older adults and males. We also find that lower ACE2 expression in epithelial cells occurs in people with asthma and is associated with reduced Furin expression and increased ADAM-17 expression. This may explain at least in part the relative sparing of people with asthma from severe COVID-19 disease.
Pressurised metered dose inhaler-spacer technique in young children improves with video instruction
Publisher: Springer Science and Business Media LLC
Date: 06-2016
DOI: 10.1007/S00431-016-2738-2
Abstract: The importance of good device technique to maximise delivery of aerosolised medications is widely recognised. Pressurised metered dose inhaler (pMDI)-spacer technique was investigated in 122 children, aged 2-7 years, with asthma. Eight in idual steps of device technique were evaluated before and after viewing an instructional video for correct device technique. Video measurements were repeated every three months for nine months. Device technique improved directly after video instruction at the baseline study visit (p < 0.001) but had no immediate effect at subsequent visits. Additionally, pMDI-spacer technique improved with successive visits over one year for the group overall as evidenced by increases in the proportion of children scoring maximal (p = 0.02) and near-maximal (p = 0.04) scores. Repeated video instruction over time improves inhaler technique in young children. • Correct device technique is considered essential for sufficient delivery of inhaled medication. • Poor inhaler use is common in young asthmatic children using pressurised metered dose inhalers and spacers. What is New: • Video instruction could be used as a strategy to improve device technique in young children.
The International Pharmacists-as-Immunizers Partnership (IPIP)—Advancing Research on Pharmacist-Administered Immunizations Worldwide
Publisher: MDPI AG
Date: 04-06-2019
Abstract: This article describes the formation of the International Pharmacists-as-Immunizers Partnership (IPIP), an international network of pharmacy practice researchers with an interest in pharmacist-administered immunizations. Using funds obtained from a university-sponsored grant, a two-day meeting was held at the University of Waterloo in Canada to discuss published and in-progress research on the topic, identify gaps and priorities for future research, and share implementation strategies used in different jurisdictions. Twelve researchers from five countries attended this initial meeting, identified from both personal networks and from authorship lists from published research. Small- and large-group discussions addressed a number of themes, including: clinical, economic and educational outcomes of the service the perspectives of pharmacists, patients, and other health professionals operational and policy factors influencing uptake safety and the immunizing pharmacist’s role in disaster preparedness. Feedback on our first meeting and outcomes achieved were evaluated on the basis of participant feedback. Key components of the meeting that were considered successful and important lessons learned are summarized, so that other like-minded researchers with a shared pharmacy practice research interest could consider leveraging funding opportunities to establish other international pharmacy practice research networks.
Use of a Primary Epithelial Cell Screening Tool to Investigate Phage Therapy in Cystic Fibrosis
Publisher: Frontiers Media SA
Date: 28-11-2018
Marrow Stromal Cells (MSC): A species Comparison
Publisher: Springer US
Date: 2003
Rhinovirus Infection Drives Complex Host Airway Molecular Responses in Children With Cystic Fibrosis.
Publisher: Frontiers Media SA
Date: 16-07-2020
Early life rhinovirus infection exacerbates house-dust-mite induced lung disease more severely in female mice
Publisher: Informa UK Limited
Date: 02-01-2016
DOI: 10.3109/01902148.2015.1131346
Abstract: Recent studies have employed animal models to investigate links between rhinovirus infection and allergic airways disease, however, most do not involve early life infection, and none consider the effects of sex on responses. Here, we infected male and female mice with human rhinovirus 1B (or control) on day 7 of life. Mice were then subjected to 7 weeks of exposure to house-dust-mite prior to assessment of bronchoalveolar inflammation, serum antibodies, lung function, and responsiveness to methacholine. There were significant differences in responses between males and females in most outcomes. In males, chronic house-dust-mite exposure increased bronchoalveolar inflammation, house-dust-mite specific IgG1 and responsiveness of the lung parenchyma, however, there was no additional impact of rhinovirus infection. Conversely, in females, there were additive and synergistic effects of rhinovirus infection and house-dust-mite exposure on neutrophilia, airway resistance, and responsiveness of the lung parenchyma. We conclude that early life rhinovirus infection influences the development of house-dust-mite induced lung disease in female, but not male mice.
Transcription factor p63 regulates key genes and wound repair in human airway epithelial Basal cells
Publisher: American Thoracic Society
Date: 12-2013
Toxicity of different biodiesel exhausts in primary human airway epithelial cells grown at air-liquid interface.
Publisher: Elsevier BV
Date: 08-2022
DOI: 10.1016/J.SCITOTENV.2022.155016
Abstract: Biodiesel is created through the transesterification of fats/oils and its usage is increasing worldwide as global warming concerns increase. Biodiesel fuel properties change depending on the feedstock used to create it. The aim of this study was to assess the different toxicological properties of biodiesel exhausts created from different feedstocks using a complex 3D air-liquid interface (ALI) model that mimics the human airway. Primary human airway epithelial cells were grown at ALI until full differentiation was achieved. Cells were then exposed to 1/20 diluted exhaust from an engine running on Diesel (ULSD), pure or 20% blended Canola biodiesel and pure or 20% blended Tallow biodiesel, or Air for control. Exhaust was analysed for various physio-chemical properties and 24-h after exposure, ALI cultures were assessed for permeability, protein release and mediator response. All measured exhaust components were within industry safety standards. ULSD contained the highest concentrations of various combustion gases. We found no differences in terms of particle characteristics for any of the tested exhausts, likely due to the high dilution used. Exposure to Tallow B100 and B20 induced increased permeability in the ALI culture and the greatest increase in mediator response in both the apical and basal compartments. In contrast, Canola B100 and B20 did not impact permeability and induced the smallest mediator response. All exhausts but Canola B20 induced increased protein release, indicating epithelial damage. Despite the concentrations of all exhausts used in this study meeting industry safety regulations, we found significant toxic effects. Tallow biodiesel was found to be the most toxic of the tested fuels and Canola the least, both for blended and pure biodiesel fuels. This suggests that the feedstock biodiesel is made from is crucial for the resulting health effects of exhaust exposure, even when not comprising the majority of fuel composition.
Rhinovirus Infection Is Associated With Airway Epithelial Cell Necrosis and Inflammation via Interleukin-1 in Young Children With Cystic Fibrosis
Publisher: Frontiers Media SA
Date: 09-04-2020
Elastase Exocytosis by Airway Neutrophils Is Associated with Early Lung Damage in Children with Cystic Fibrosis
Publisher: American Thoracic Society
Date: 04-2019
Progress in Model Systems of Cystic Fibrosis Mucosal Inflammation to Understand Aberrant Neutrophil Activity
Publisher: Frontiers Media SA
Date: 07-04-2020
Viral Induced Effects on a Vulnerable Epithelium; Lessons Learned From Paediatric Asthma and Eosinophilic Oesophagitis
Publisher: Frontiers Media SA
Date: 29-11-2021
DOI: 10.3389/FIMMU.2021.773600
Abstract: The epithelium is integral to the protection of many different biological systems and for the maintenance of biochemical homeostasis. Emerging evidence suggests that particular children have epithelial vulnerabilities leading to dysregulated barrier function and integrity, that resultantly contributes to disease pathogenesis. These epithelial vulnerabilities likely develop in utero or in early life due to various genetic, epigenetic and environmental factors. Although various epithelia are uniquely structured with specific function, prevalent allergic-type epithelial diseases in children potentially have common or parallel disease processes. These include inflammation and immune response dysregulation stemming from atypical epithelial barrier function and integrity. Two diseases where aetiology and pathogenesis are potentially linked to epithelial vulnerabilities include Paediatric Asthma and Eosinophilic Oesophagitis (EoE). For ex le, rhinovirus C (RV-C) is a known risk factor for paediatric asthma development and is known to disrupt respiratory epithelial barrier function causing acute inflammation. In addition, EoE, a prevalent atopic condition of the oesophageal epithelium, is characterised by similar innate immune and epithelial responses to viral injury. This review examines the current literature and identifies the gaps in the field defining viral-induced effects on a vulnerable respiratory epithelium and resulting chronic inflammation, drawing from knowledge generated in acute wheezing illness, paediatric asthma and EoE. Besides highlighting the importance of epithelial structure and barrier function in allergic disease pathogenesis regardless of specific epithelial sub-types, this review focuses on the importance of examining other parallel allergic-type disease processes that may uncover commonalities driving disease pathogenesis. This in turn may be beneficial in the development of common therapeutics for current clinical management and disease prevention in the future.
Small macrophages are present in early childhood respiratory disease
Publisher: Elsevier BV
Date: 05-2012
DOI: 10.1016/J.JCF.2011.11.008
Abstract: Recently, an established "small macrophage" phenotype has been observed in the sputum of patients with CF and COPD. However, little is known about the prevalence of this phenotype in the airways of young children. Since respiratory inflammation begins early in CF, we hypothesised that these small macrophages would be increased in paediatric CF bronchoalveolar lavage (BAL). Macrophage populations in CF and disease control BAL were assessed by multicolour flow cytometry. BAL inflammatory indices were collected as part of the AREST-CF programme. Small macrophages were present in CF (n=35, mean 36±12% of BAL macrophages) but not significantly different to the respiratory disease controls (n=7, mean 40±21%). Number of small macrophages correlated significantly with number of BAL neutrophils (r=0.44, p<0.01) but not infection or IL-8. In paediatric patients small macrophages are not unique to CF, but their establishment as the dominant phenotype in adults may be due to chronicity of inflammation and infection.
Effect of iron chelators on proliferation and iron uptake in hepatoma cells
Publisher: Wiley
Date: 2001
DOI: 10.1002/1097-0142(20011215)92:12<3093::AID-CNCR10107>3.0.CO;2-B
Abstract: The siderophore desferrioxamine mesylate (DFO) is used routinely in clinical practice to treat diseases of iron (Fe) overload. Recent studies suggest that DFO and other chelators may have potential in the treatment of cancer. The current study reports the findings obtained when a number of chelators with varying membrane permeability, Fe-binding affinity, and preference for either Fe(3+) or Fe(2+) were assessed for their antineoplastic potential in vitro against hepatocellular carcinoma cells (HCC) because to the authors' knowledge there are few effective treatment methods for this aggressive neoplasm. A number of criteria were investigated, including the effects of the chelators on cell proliferation, selectivity, Fe uptake, toxicity, and cell cycle progression. The results obtained showed that Fe binding affinity did appear to influence Fe chelator activity but was not an absolute factor, and that certain ferric and ferrous, membrane-permeable and membrane-impermeable Fe chelators demonstrated antiproliferative activity and selectivity against HCC. All effective chelators inhibited Fe uptake from Tf-(59)Fe in both hepatoma cells and normal hepatocytes. However, these chelators all had much lower effects on the survival of normal proliferating and nonproliferating cells. The effects on cell cycle were more varied between chelators, as were levels of toxicity. The results of the current study indicate that a number of different Fe chelators have the potential to treat HCC, and that further investigation into their mechanisms of action is warranted.
Macrophage PD-1 associates with neutrophilia and reduced bacterial killing in early cystic fibrosis airway disease
Publisher: Elsevier BV
Date: 11-2022
DOI: 10.1016/J.JCF.2022.06.001
Abstract: Macrophages are the major resident immune cells in human airways coordinating responses to infection and injury. In cystic fibrosis (CF), neutrophils are recruited to the airways shortly after birth, and actively exocytose damaging enzymes prior to chronic infection, suggesting a potential defect in macrophage immunomodulatory function. Signaling through the exhaustion marker programmed death protein 1 (PD-1) controls macrophage function in cancer, sepsis, and airway infection. Therefore, we sought to identify potential associations between macrophage PD-1 and markers of airway disease in children with CF. Blood and bronchoalveolar lavage fluid (BALF) were collected from 45 children with CF aged 3 to 62 months and structural lung damage was quantified by computed tomography. The phenotype of airway leukocytes was assessed by flow cytometry, while the release of enzymes and immunomodulatory mediators by molecular assays. Airway macrophage PD-1 expression correlated positively with structural lung damage, neutrophilic inflammation, and infection. Interestingly, even in the absence of detectable infection, macrophage PD-1 expression was elevated and correlated with neutrophilic inflammation. In an in vitro model mimicking leukocyte recruitment into CF airways, soluble mediators derived from recruited neutrophils directly induced PD-1 expression on recruited monocytes/macrophages, suggesting a causal link between neutrophilic inflammation and macrophage PD-1 expression in CF. Finally, blockade of PD-1 in a short-term culture of CF BALF leukocytes resulted in improved pathogen clearance. Taken together, these findings suggest that in early CF lung disease, PD-1 upregulation associates with airway macrophage exhaustion, neutrophil takeover, infection, and structural damage.
Limbal stem cells: The search for a marker
Publisher: Wiley
Date: 2006
DOI: 10.1111/J.1442-9071.2006.01147.X
Abstract: The corneal epithelium is a self-renewing tissue and must, by definition, have a resident basal cell population necessary for homeostasis and wound healing. There is a substantial body of evidence, both experimental and clinical, pointing to the basal cells of the limbus as the location of corneal epithelial stem cells. However, in the absence of a definitive marker of limbal stem cells, the evidence remains largely circumstantial. Many markers such as p63 and integrin alpha9 are preferentially localized to the limbus but cannot be regarded as stem cell-specific. Other markers such as K3 and connexin 43 can be regarded as markers of corneal differentiation. The discovery of stem cell markers in other organ systems, such as the haematopoietic system, offers optimism that a marker of limbal stem cells will one day be found. Such a discovery will have far-reaching implications for the study of ocular surface biology and stratified squamous epithelia in general.
Complete Genomes of Three Pseudomonas aeruginosa Bacteriophages, Kara-mokiny 1, Kara-mokiny 2, and Kara-mokiny 3
Publisher: American Society for Microbiology
Date: 15-12-2022
DOI: 10.1128/MRA.00955-22
Abstract: Here, we present the complete genome sequence of Pseudomonas aeruginosa phages Kara-mokiny 1, Kara-mokiny 2, and Kara-mokiny 3. These phages have lytic capabilities against P. aeruginosa and belong to the myovirus morphotype. The genomes of Kara-mokiny 1 and Kara-mokiny 2 are 67,075 bp while that of Kara-mokiny 3 is 66,019 bp long.
House dust mite induced lung inflammation does not alter circulating vitamin D levels
Publisher: Public Library of Science (PLoS)
Date: 12-11-2014
Using Stem Cells to Repair the Degenerate Retina
Publisher: Springer US
Date: 2006
Development and validation of a miniaturized bacteriophage host range screening assay against antibiotic resistant Pseudomonas aeruginosa.
Publisher: Elsevier BV
Date: 11-2021
DOI: 10.1016/J.MIMET.2021.106346
Abstract: Antimicrobial resistance is a current global health crisis, and the increasing emergence of multidrug resistant infections has led to the resurgent interest in bacteriophages as an alternative treatment. Prior to clinical application, phage suitability is assessed, via susceptibility testing and breadth of host range to bacteriophage, however, these are both large-scale manual processes and labor-intensive. The aim of the study was to establish and validate a scaled down methodology for high-throughput screening to reduce procedural footprint. In this paper, we describe a scaled-down adapted methodology that can successfully screen bacteriophages, isolated and purified from wastewater s les. Furthermore, we describe a miniaturized host range assay against clinical Pseudomonas aeruginosa isolates using a spot test (2 μL/ drop) that was found to be both sensitive (94.6%) and specific (94.7%). It also demonstrated a positive predictive value (PPV) of 86.4% and negative predictive value (NPV) of 98%. The breadth of host range of bacteriophages that exhibited lytic activity on P. aeruginosa isolates was corroborated using the scaled down assay. The high correlation achieved in this study confirms miniaturization as the first step in future automation that could test phage ersity and efficacy as antimicrobials.
Soy Biodiesel Exhaust is More Toxic than Mineral Diesel Exhaust in Primary Human Airway Epithelial Cells.
Publisher: American Chemical Society (ACS)
Date: 27-08-2019
Abstract: As global biodiesel production increases, there are concerns over the potential health impact of exposure to the exhaust, particularly in regard to young children who are at high risk because of their continuing lung development. Using human airway epithelial cells obtained from young children, we compared the effects of exposure to exhaust generated by a diesel engine with Euro V/VI emission controls running on conventional diesel (ultra-low-sulfur mineral diesel, ULSD), soy biodiesel (B100), or a 20% blend of soy biodiesel with diesel (B20). The exhaust output of biodiesel was found to contain significantly more respiratory irritants, including NO
DNA methylation profiles of airway epithelial cells and PBMCs from healthy, atopic and asthmatic children.
Publisher: Public Library of Science (PLoS)
Date: 06-09-2012
Inducible NO synthase expression is low in airway epithelium from young children with cystic fibrosis
Publisher: BMJ
Date: 06-2006
Biodiesel exhaust: The need for a systematic approach to health effects research
Publisher: Wiley
Date: 14-07-2015
DOI: 10.1111/RESP.12587
Abstract: Biodiesel is a generic term for fuel that can be made from virtually any plant or animal oil via transesterification of triglycerides with an alcohol (and usually a catalyst). Biodiesel has received considerable scientific attention in recent years, as it is a renewable resource that is directly able to replace mineral diesel in many engines. Additionally, some countries have mandated a minimum biodiesel content in all diesel fuel sold on environmental grounds. When combusted, biodiesel produces exhaust emissions containing particulate matter, adsorbed chemicals and a range of gases. In many cases, absolute amounts of these pollutants are lower in biodiesel exhaust compared with mineral diesel exhaust, leading to speculation that biodiesel exhaust may be less harmful to health. Additionally, engine performance studies show that the concentrations of these pollutants vary significantly depending on the renewable oil used to make the biodiesel and the ratio of biodiesel to mineral diesel in the fuel mix. Given the strategic and legislative push towards the use of biodiesel in many countries, a concerning possibility is that certain biodiesels may produce exhaust emissions that are more harmful to health than others. This variation suggests that a comprehensive, systematic and comparative approach to assessing the potential for a range of different biodiesel exhausts to affect health is urgently required. Such an assessment could inform biodiesel production priorities, drive research and development into new exhaust treatment technologies, and ultimately minimize the health impacts of biodiesel exhaust exposure.
ACE2 expression is elevated in airway epithelial cells from older and male healthy individuals but reduced in asthma
Publisher: Wiley
Date: 17-01-2021
DOI: 10.1111/RESP.14003
Abstract: COVID‐19 is complicated by acute lung injury, and death in some in iduals. It is caused by SARS‐CoV‐2 that requires the ACE2 receptor and serine proteases to enter AEC. We determined what factors are associated with ACE2 expression particularly in patients with asthma and COPD. We obtained lower AEC from 145 people from two independent cohorts, aged 2–89 years, Newcastle ( n = 115) and Perth ( n = 30), Australia. The Newcastle cohort was enriched with people with asthma ( n = 37) and COPD ( n = 38). Gene expression for ACE2 and other genes potentially associated with SARS‐CoV‐2 cell entry was assessed by qPCR, and protein expression was confirmed with immunohistochemistry on endobronchial biopsies and cultured AEC. Increased gene expression of ACE2 was associated with older age ( P = 0.03) and male sex ( P = 0.03), but not with pack‐years smoked. When we compared gene expression between adults with asthma, COPD and healthy controls, mean ACE2 expression was lower in asthma patients ( P = 0.01). Gene expression of furin, a protease that facilitates viral endocytosis, was also lower in patients with asthma ( P = 0.02), while ADAM‐17, a disintegrin that cleaves ACE2 from the surface, was increased ( P = 0.02). ACE2 protein expression was also reduced in endobronchial biopsies from asthma patients. Increased ACE2 expression occurs in older people and males. Asthma patients have reduced expression. Altered ACE2 expression in the lower airway may be an important factor in virus tropism and may in part explain susceptibility factors and why asthma patients are not over‐represented in those with COVID‐19 complications.
Matrix metalloproteinase activation by free neutrophil elastase contributes to bronchiectasis progression in early cystic fibrosis.
Publisher: European Respiratory Society (ERS)
Date: 30-04-2015
DOI: 10.1183/09031936.00212114
Abstract: Neutrophil elastase is the most significant predictor of bronchiectasis in early-life cystic fibrosis however, the causal link between neutrophil elastase and airway damage is not well understood. Matrix metalloproteinases (MMPs) play a crucial role in extracellular matrix modelling and are activated by neutrophil elastase. The aim of this study was to assess if MMP activation positively correlates with neutrophil elastase activity, disease severity and bronchiectasis in young children with cystic fibrosis. Total MMP-1, MMP-2, MMP-7, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-1 levels were measured in bronchoalveolar lavage fluid collected from young children with cystic fibrosis during annual clinical assessment. Active ro-enzyme ratio of MMP-9 was determined by gelatin zymography. Annual chest computed tomography imaging was scored for bronchiectasis. A higher MMP-9/TIMP-1 ratio was associated with free neutrophil elastase activity. In contrast, MMP-2/TIMP-2 ratio decreased and MMP-1 and MMP-7 were not detected in the majority of s les. Ratio of active ro-enzyme MMP-9 was also higher in the presence of free neutrophil elastase activity, but not infection. Across the study cohort, both MMP-9/TIMP-1 and active MMP-9 were associated with progression of bronchiectasis. Both MMP-9/TIMP-1 and active MMP-9 increased with free neutrophil elastase and were associated with bronchiectasis, further demonstrating that free neutrophil elastase activity should be considered an important precursor to cystic fibrosis structural disease.
Epithelial Mesenchymal Transition in Respiratory Disease
Publisher: Elsevier BV
Date: 06-2020
Azithromycin reduces airway inflammation induced by human rhinovirus in lung allograft recipients.
Publisher: Wiley
Date: 15-04-2019
DOI: 10.1111/RESP.13550
Abstract: Human rhinovirus (RV) is a common upper and lower respiratory pathogen in lung allograft recipients causing respiratory tract exacerbation and contributing towards allograft dysfunction and long-term lung decline. In this study, we tested the hypothesis that RV could infect both the small and large airways, resulting in significant inflammation. Matched large and small airway epithelial cells (AEC) were obtained from five lung allograft recipients. Primary cultures were established, and monolayers were infected with RV1b over time with varying viral titre. Cell viability, receptor expression, viral copy number, apoptotic induction and inflammatory cytokine production were also assessed at each region. Finally, the effect of azithromycin on viral replication, induction of apoptosis and inflammation was investigated. RV infection caused significant cytotoxicity in both large AEC (LAEC) and small AEC (SAEC), and induced a similar apoptotic response in both regions. There was a significant increase in receptor expression in the LAEC only post viral infection. Viral replication was elevated in both LAEC and SAEC, but was not significantly different. Prophylactic treatment of azithromycin reduced viral replication and d ened the production of inflammatory cytokines post-infection. Our data illustrate that RV infection is capable of infecting upper and lower AEC, driving cell death and inflammation. Prophylactic treatment with azithromycin was found to mitigate some of the detrimental responses. Findings provide further support for the prophylactic prescription of azithromycin to minimize the impact of RV infection.
Investigating the Implications of CFTR Exon Skipping Using a Cftr Exon 9 Deleted Mouse Model
Publisher: Frontiers Media SA
Date: 22-03-2022
DOI: 10.3389/FPHAR.2022.868863
Abstract: Introduction: Severity and disease progression in people with Cystic Fibrosis (CF) is typically dependent on their genotype. One potential therapeutic strategy for people with specific mutations is exon skipping with antisense oligonucleotides (AO). CFTR exon 9 is an in-frame exon and hence the exclusion of this exon would excise only 31 amino acids but not alter the reading frame of the remaining mRNA. Splice mutations 1209 + 1 G & C and 1209 + 2 T & G were documented to cause CFTR exon 9 skipping and these variants were reported to manifest as a milder CF disease, therefore exon 9 skipping could be beneficial for people with class I mutations that affect exon 9 such as p.Trp401X. While the impact of exon 9 skipping on gene expression and cellular pathways can be studied in cells in vitro , trace amount of full-length normal or mutated material could confound the evaluation. To overcome this limitation, the impact of CFTR exon 9 skipping on disease phenotype and severity is more effectively evaluated in a small animal model. It was hypothesised that antisense oligonucleotide-mediated skipping this particular exon could result in a “mild mouse CF phenotype”. Methods: Cftr exon 9 deleted mice were generated using homologous recombination. Survival of homozygous ( Cftr Δ9/Δ9 ) and heterozygous ( Cftr Δ9/+ ) mice was compared to that of other CF mouse models, and lung and intestinal organ histology examined for any pathologies. Primary airway epithelial cells (pAECs) were harvested from Cftr Δ9/Δ9 mice and cultured at the Air Liquid Interface for CFTR functional assessment using Ussing Chamber analysis. Results: A Cftr Δ9/Δ9 mouse model presented with intestinal obstructions, and at time of weaning (21 days). Cftr Δ9/Δ9 mice had a survival rate of 83% that dropped to 38% by day 50. Histological sections of the small intestine from Cftr Δ9/Δ9 mice showed more goblet cells and mucus accumulation than s les from the Cftr Δ9/+ littermates. Airway epithelial cell cultures established from Cftr Δ9/Δ9 mice were not responsive to forskolin stimulation. Summary: The effect of Cftr exon 9 deletion on Cftr function was assessed and it was determined that the encoded Cftr isoform did not result in a milder “mouse CF disease phenotype,” suggesting that Cftr exon 9 is not dispensable, although further investigation in human CF pAECs would be required to confirm this observation.
COVID-19 monitoring with sparse sampling of sewered and non-sewered wastewater in urban and rural communities
Publisher: Elsevier BV
Date: 07-2023
Genome Sequences of Two Lytic Staphylococcus aureus Bacteriophages Isolated from Wastewater
Publisher: American Society for Microbiology
Date: 15-12-2022
DOI: 10.1128/MRA.00954-22
Abstract: Two lytic double-stranded DNA (dsDNA) bacteriophages, belonging to the family Herelleviridae , were isolated from wastewater in Western Australia. Biyabeda-mokiny 2 appears to belong to the genus Kayvirus , and Koomba-kaat 1 to Silviavirus .
Are stem cell characteristics altered by disease state?
Publisher: Mary Ann Liebert Inc
Date: 02-2005
Abstract: Autologous stem cell transplantation combined with gene therapy can potentially be used to treat genetically inherited diseases. However, characterization of multipotential cells from a disease state remains extremely limited. We have characterized adult bone marrow stromal cells (MSCs) derived from three retinal degenerative mouse models and compared them to marrow stromal cells derived from their normal strain counterparts. Despite similar profiles soon after harvest, at 30 days postisolation, marrow stromal cells derived from a disease origin were shown to contain a large pool (approximately 89-99%) of undifferentiated marrow stromal cells (CD90(+)/STRO-1(+)) as compared to their normal counterparts (approximately 19-43%). Fetal bovine serum appeared essential for marrow stromal cell proliferation and was not found to induce differentiation, although it could be substituted with other additives including epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and leukemia inhibitory factor (LIF). We also showed that resulting CD90(+)/STRO(+) cells derived from both states could be directed into desired lineages expressing at the same rate and that they could be transduced with the same efficiency using different viral vehicles. This investigation has shown the existence of a large pool of undifferentiated stem cells derived from the disease state that have the potential to form the desired cell types when appropriately cued.
Complete Genome Sequences of Four Pseudomonas aeruginosa Bacteriophages: Kara-mokiny 8, Kara-mokiny 13, Kara-mokiny 16, and Boorn-mokiny 1
Publisher: American Society for Microbiology
Date: 15-12-2022
DOI: 10.1128/MRA.00960-22
Abstract: Pseudomonas aeruginosa is an opportunistic pathogen. Here, we report the isolation of four bacteriophages from wastewater. All four bacteriophages belong to the Myoviridae family. Kara-mokiny 8, 13, and 16 are of the Pbunavirus genus and have genomes between 65,527 and 66,420-bp. Boorn-mokiny 1 is of the Phikzvirus genus and has a 278,796-bp genome.
Pediatric nasal epithelial cells are less permissive to SARS-CoV-2 replication compared to adult cells
Publisher: Cold Spring Harbor Laboratory
Date: 08-03-2021
DOI: 10.1101/2021.03.08.434300
Abstract: Children typically experience more mild symptoms of COVID-19 when compared to adults. There is a strong body of evidence that children are also less susceptible to SARS-CoV-2 infection with the ancestral viral isolate. However, the emergence of SARS-CoV-2 variants of concern (VOCs) has been associated with an increased number of pediatric infections. Whether this is the result of widespread adult vaccination or fundamental changes in the biology of SARS-CoV-2 remains to be determined. Here, we use primary nasal epithelial cells from children and adults, differentiated at an air-liquid interface to show that the ancestral SARS-CoV-2 replicates to significantly lower titers in the nasal epithelial cells of children compared to those of adults. This was associated with a heightened antiviral response to SARS-CoV-2 in the nasal epithelial cells of children. Importantly, the Delta variant also replicated to significantly lower titres in the nasal epithelial cells of children. This trend was markedly less pronounced in the case of Omicron. It is also striking to note that, at least in terms of viral RNA, Omicron replicated better in pediatric NECs compared to both Delta and the ancestral virus. Taken together, these data show that the nasal epithelium of children supports lower infection and replication of ancestral SARS-CoV-2, although this may be changing as the virus evolves.
Blocking Notch3 Signaling Abolishes MUC5AC Production in Airway Epithelial Cells from Asthmatics.
Publisher: American Thoracic Society
Date: 06-2202
The airway epithelium is a direct source of matrix degrading enzymes in bronchiolitis obliterans syndrome.
Publisher: Elsevier BV
Date: 10-2011
DOI: 10.1016/J.HEALUN.2011.06.007
Abstract: Long-term survival after lung transplantation is hindered by the development of bronchiolitis obliterans syndrome (BOS), and recent evidence suggests that dysregulated epithelial repair may underlie its development. Because matrix metalloproteinase (MMP) -2 and MMP-9 secretion is integral to repair, we hypothesized that airway epithelial cells from patients with BOS would over-express these matrix-degrading enzymes. Cells obtained from bronchial and bronchiolar brushings from patients with and without BOS (without acute rejection or infection) were analyzed via quantitative polymerase chain reaction and immunocytochemistry for MMP-2, and MMP-9 gene and protein expression. The expression of tissue inhibitor of metalloproteinase (TIMP)2 and TIMP1 was also assessed. MMP activity in bronchoalveolar lavage was determined via gelatin zymography. MMP-2 and MMP-9 production was significantly higher in bronchoalveolar lavage (3.85- and 11.59-fold, p < 0.001) and airway epithelium (MMP-2 bronchial: 6.33-fold, bronchiolar: 3.57-fold, both p < 0.001 MMP-9 bronchial: 32.55-fold, p < 0.001 bronchiolar: 8.60-fold, p = 0.01) in patients with BOS, but expression in patients without BOS was not different from healthy controls. TIMP expression was similar in patients with and without BOS. Immunostaining confirmed that the airway epithelium was a direct source of MMP-2 and MMP-9 expression in patients with BOS. In patients with BOS, the airway epithelium over-expresses MMPs, even in the absence of acute rejection or infection. Dysregulated epithelial repair may be a key feature of BOS.
Editorial: Emerging Therapeutic Approaches for Cystic Fibrosis.
Publisher: Frontiers Media SA
Date: 29-11-2019
Airway epithelial repair in health and disease: Orchestrator or simply a player?
Publisher: Wiley
Date: 25-01-2016
DOI: 10.1111/RESP.12731
Abstract: Epithelial cells represent the most important surface of contact in the body and form the first line of defence of the body to external environment. Consequently, epithelia have numerous roles in order to maintain a homeostatic defence barrier. Although the epithelium has been extensively studied over several decades, it remains the focus of new research, indicating a lack of understanding that continues to exist around these cells in specific disease settings. Importantly, evidence is emerging that airway epithelial cells in particular have varied complex functions rather than simple passive roles. One area of current interest is its role following injury. In particular, the epithelial-specific cellular mechanisms regulating their migration during wound repair remain poorly understood and remain an area that requires much needed investigation. A better understanding of the physiological, cellular and molecular wound repair mechanisms could assist in elucidating pathological processes that contribute to airway epithelial pathology. This review attempts to highlight migration-specific and cell-extracellular matrix (ECM) aspects of repair used by epithelial cells under normal and disease settings, in the context of human airways.
The potential of marrow stromal cells in stem cell therapy
Publisher: Springer Science and Business Media LLC
Date: 11-2001
DOI: 10.1038/EYE.2001.233
Fuel feedstock determines biodiesel exhaust toxicity in a human airway epithelial cell exposure model.
Publisher: Elsevier BV
Date: 10-2021
DOI: 10.1016/J.JHAZMAT.2021.126637
Abstract: Biodiesel is promoted as a sustainable replacement for commercial diesel. Biodiesel fuel and exhaust properties change depending on the base feedstock oil/fat used during creation. The aims of this study were, for the first time, to compare the exhaust exposure health impacts of a wide range of biodiesels made from different feedstocks and relate these effects with the corresponding exhaust characteristics. Primary airway epithelial cells were exposed to diluted exhaust from an engine running on conventional diesel and biodiesel made from Soy, Canola, Waste Cooking Oil, Tallow, Palm and Cottonseed. Exhaust properties and cellular viability and mediator release were analysed post exposure. The exhaust physico-chemistry of Tallow biodiesel was the most different to diesel as well as the most toxic, with exposure resulting in significantly decreased cellular viability (95.8 ± 6.5%) and increased release of several immune mediators including IL-6 (+223.11 ± 368.83 pg/mL) and IL-8 (+1516.17 ± 2908.79 pg/mL) above Air controls. In contrast Canola biodiesel was the least toxic with exposure only increasing TNF-α (4.91 ± 8.61). This study, which investigated the toxic effects for the largest range of biodiesels, shows that exposure to different exhausts results in a spectrum of toxic effects in vitro when combusted under identical conditions.
Stability Considerations for Bacteriophages in Liquid Formulations Designed for Nebulization
Publisher: MDPI AG
Date: 12-08-2023
Abstract: Pulmonary bacterial infections present a significant health risk to those with chronic respiratory diseases (CRDs) including cystic fibrosis (CF) and chronic-obstructive pulmonary disease (COPD). With the emergence of antimicrobial resistance (AMR), novel therapeutics are desperately needed to combat the emergence of resistant superbugs. Phage therapy is one possible alternative or adjunct to current antibiotics with activity against antimicrobial-resistant pathogens. How phages are administered will depend on the site of infection. For respiratory infections, a number of factors must be considered to deliver active phages to sites deep within the lung. The inhalation of phages via nebulization is a promising method of delivery to distal lung sites however, it has been shown to result in a loss of phage viability. Although preliminary studies have assessed the use of nebulization for phage therapy both in vitro and in vivo, the factors that determine phage stability during nebulized delivery have yet to be characterized. This review summarizes current findings on the formulation and stability of liquid phage formulations designed for nebulization, providing insights to maximize phage stability and bactericidal activity via this delivery method.
AI-Driven Cell Tracking to Enable High-Throughput Drug Screening Targeting Airway Epithelial Repair for Children with Asthma
Publisher: MDPI AG
Date: 17-05-2022
DOI: 10.3390/JPM12050809
Abstract: The airway epithelium of children with asthma is characterized by aberrant repair that may be therapeutically modifiable. The development of epithelial-targeting therapeutics that enhance airway repair could provide a novel treatment avenue for childhood asthma. Drug discovery efforts utilizing high-throughput live cell imaging of patient-derived airway epithelial culture-based wound repair assays can be used to identify compounds that modulate airway repair in childhood asthma. Manual cell tracking has been used to determine cell trajectories and wound closure rates, but is time consuming, subject to bias, and infeasible for high-throughput experiments. We therefore developed software, EPIC, that automatically tracks low-resolution low-framerate cells using artificial intelligence, analyzes high-throughput drug screening experiments and produces multiple wound repair metrics and publication-ready figures. Additionally, unlike available cell trackers that perform cell segmentation, EPIC tracks cells using bounding boxes and thus has simpler and faster training data generation requirements for researchers working with other cell types. EPIC outperformed publicly available software in our wound repair datasets by achieving human-level cell tracking accuracy in a fraction of the time. We also showed that EPIC is not limited to airway epithelial repair for children with asthma but can be applied in other cellular contexts by outperforming the same software in the Cell Tracking with Mitosis Detection Challenge (CTMC) dataset. The CTMC is the only established cell tracking benchmark dataset that is designed for cell trackers utilizing bounding boxes. We expect our open-source and easy-to-use software to enable high-throughput drug screening targeting airway epithelial repair for children with asthma.
Preterm birth: Born too soon for the developing airway epithelium?
Publisher: Elsevier BV
Date: 08-2019
DOI: 10.1016/J.PRRV.2018.11.003
Abstract: Birth prior to term interrupts the normal development of the respiratory system and consequently results in poor respiratory outcomes that persist throughout childhood. The mechanisms underpinning these poor respiratory outcomes are not well understood, but intrinsic abnormalities within the airway epithelium may be a contributing factor. Current evidence suggests that the airway epithelium is both structurally and functionally abnormal after preterm birth, with reports of epithelial thickening and goblet cell hyperplasia in addition to increased inflammation and apoptosis in the neonatal intensive care unit. However, studies focusing on the airway epithelium are limited and many questions remain unanswered including whether abnormalities are a direct result of interrupted development, a consequence of exposure to inflammatory stimuli in the perinatal period or a combination of the two. In addition, the difficulty of accessing airway tissue has resulted in the majority of evidence being collected in the pre-surfactant era which may not reflect contemporary preterm birth. This review examines the consequences of preterm birth on the airway epithelium and explores the clinical relevance of currently available models whilst highlighting the need to develop a clinically relevant in vitro model to help further our understanding of the airway epithelium in preterm birth.
Biodiesel Exhaust Toxicity with and without Diethylene Glycol Dimethyl Ether Fuel Additive in Primary Airway Epithelial Cells Grown at the Air-Liquid Interface.
Publisher: American Chemical Society (ACS)
Date: 30-09-2022
Abstract: Biodiesel usage is increasing steadily worldwide as the push for renewable fuel sources increases. The increased oxygen content in biodiesel fuel is believed to cause decreased particulate matter (PM) and increased nitrous oxides within its exhaust. The addition of fuel additives to further increase the oxygen content may contribute to even further benefits in exhaust composition. The aim of this study was to assess the toxicity of 10% (v/v) diethylene glycol dimethyl ether (DGDME) added as a biodiesel fuel additive. Primary human airway epithelial cells were grown at the air-liquid interface and exposed to diluted exhaust from an engine running on either grapeseed, bran, or coconut biodiesel or the same three biodiesels with 10% (v/v) DGDME added to them mineral diesel and air were used as controls. Exhaust properties, culture permeability, epithelial cell damage, and IL-6 and IL-8 release were measured postexposure. The fuel additive DGDME caused a decrease in PM and nitrous oxide concentrations. However, exhaust exposure with DGDME also caused decreased permeability, increased epithelial cell damage, and increased release of IL-6 and IL-8 (
Determinants of culture success in an airway epithelium sampling program of young children with cystic fibrosis.
Publisher: Informa UK Limited
Date: 05-09-2014
DOI: 10.3109/01902148.2014.946631
Abstract: The bronchial brushing technique presents an opportunity to establish a gold standard in vitro model of Cystic Fibrosis (CF) airway disease. However, unique obstacles exist when establishing CF airway epithelial cells (pAECCF). We aimed to identify determinants of culture success through retrospective analysis of a program of routinely brushing children with CF. Anaesthetised children (CF and non-CF) had airway s les taken which were immediately processed for cell culture. Airway data for the CF cohort was obtained from clinical records and the AREST CF database. Of 260 brushings processed for culture, 114 (43.8%) pAECCF successfully cultured to passage one (P1) and 63 (24.2% of total) progressed to passage two (P2). However, >80% of non-CF specimens (pAECnon-CF) cultured to P2 from similar cell numbers. Within the CF cohort, specimens successfully cultured to P2 had a higher initial cell count and lower proportion of severe CF mutation phenotype than those that did not proliferate beyond initial seeding. Elevated airway IL-8 concentration was also negatively associated with culture establishment. Contamination by opportunistic pathogens was observed in 81 (31.2% of total) cultures and brushings from children with lower respiratory tract infections were more likely to co-culture contaminating flora. Lower passage rates of pAECCF cultures uniquely contrasts with pAECnon-CF despite similar cell numbers. An equivalent establishment rate of CF nasal epithelium reported elsewhere, significant associations to CFTR mutation phenotype, elevated airway IL-8 and opportunistic pathogens all suggest this is likely related to the CF disease milieu.
Overcoming Challenges to Make Bacteriophage Therapy Standard Clinical Treatment Practice for Cystic Fibrosis.
Publisher: Frontiers Media SA
Date: 11-01-2020
DOI: 10.3389/FMICB.2020.593988
Abstract: In iduals with cystic fibrosis (CF) are given antimicrobials as prophylaxis against bacterial lung infection, which contributes to the growing emergence of multidrug resistant (MDR) pathogens isolated. Pathogens such as Pseudomonas aeruginosa that are commonly isolated from in iduals with CF are armed with an arsenal of protective and virulence mechanisms, complicating eradication and treatment strategies. While translation of phage therapy into standard care for CF has been explored, challenges such as the lack of an appropriate animal model demonstrating safety in vivo exist. In this review, we have discussed and provided some insights in the use of primary airway epithelial cells to represent the mucoenvironment of the CF lungs to demonstrate safety and efficacy of phage therapy. The combination of phage therapy and antimicrobials is gaining attention and has the potential to delay the onset of MDR infections. It is evident that efforts to translate phage therapy into standard clinical practice have gained traction in the past 5 years. Ultimately, collaboration, transparency in data publications and standardized policies are needed for clinical translation.
Biodiesel feedstock determines exhaust toxicity in 20% biodiesel: 80% mineral diesel blends
Publisher: Elsevier BV
Date: 2023
DOI: 10.1016/J.CHEMOSPHERE.2022.136873
Abstract: To address climate change concerns, and reduce the carbon footprint caused by fossil fuel use, it is likely that blend ratios of renewable biodiesel with commercial mineral diesel fuel will steadily increase, resulting in biodiesel use becoming more widespread. Exhaust toxicity of unblended biodiesels changes depending on feedstock type, however the effect of feedstock on blended fuels is less well known. The aim of this study was to assess the impact of biodiesel feedstock on exhaust toxicity of 20% blended biodiesel fuels (B20). Primary human airway epithelial cells were exposed to exhaust diluted 1/15 with air from an engine running on conventional ultra-low sulfur diesel (ULSD) or 20% blends of soy, canola, waste cooking oil (WCO), tallow, palm or cottonseed biodiesel in diesel. Physico-chemical exhaust properties were compared between fuels and the post-exposure effect of exhaust on cellular viability and media release was assessed 24 h later. Exhaust properties changed significantly between all fuels with cottonseed B20 being the most different to both ULSD and its respective unblended biodiesel. Exposure to palm B20 resulted in significantly decreased cellular viability (96.3 ± 1.7% p < 0.01) whereas exposure to soy B20 generated the greatest number of changes in mediator release (including IL-6, IL-8 and TNF-α, p < 0.05) when compared to air exposed controls, with palm B20 and tallow B20 closely following. In contrast, canola B20 and WCO B20 were the least toxic with only mediators G-CSF and TNF-α being significantly increased. Therefore, exposure to palm B20, soy B20 and tallow B20 were found to be the most toxic and exposure to canola B20 and WCO B20 the least. The top three most toxic and the bottom three least toxic B20 fuels are consistent with their unblended counterparts, suggesting that feedstock type greatly impacts exhaust toxicity, even when biodiesel only comprises 20% of the fuel.
Aberrant cell migration contributes to defective airway epithelial repair in childhood wheeze.
Publisher: American Society for Clinical Investigation
Date: 09-04-2020
Pseudomonas aeruginosa modulates neutrophil granule exocytosis in an in vitro model of airway infection
Publisher: Wiley
Date: 11-04-2022
DOI: 10.1111/IMCB.12547
Abstract: A population of neutrophils recruited into cystic fibrosis (CF) airways is associated with proteolytic lung damage, exhibiting high expression of primary granule exocytosis marker CD63 and reduced phagocytic receptor CD16. Causative factors for this population are unknown, limiting intervention. Here we present a laboratory model to characterize responses of differentiated airway epithelium and neutrophils following respiratory infection. Pediatric primary airway epithelial cells were cultured at the air–liquid interface, challenged in idually or in combination with rhinovirus (RV) and Pseudomonas aeruginosa , then apically washed with medical saline to s le epithelial infection milieus. Cytokine multiplex analysis revealed epithelial antiviral signals, including IP‐10 and RANTES, increased with exclusive RV infection but were diminished if P. aeruginosa was also present. Proinflammatory signals interleukin‐1α and β were dominant in P. aeruginosa infection milieus. Infection washes were also applied to a published model of neutrophil transmigration into the airways. Neutrophils migrating into bacterial and viral–bacterial co‐infection milieus exhibited the in vivo CF phenotype of increased CD63 expression and reduced CD16 expression, while neutrophils migrating into milieus of RV‐infected or uninfected cultures did not. In idually, bacterial products lipopolysaccharide and N ‐formylmethionyl‐leucyl‐phenylalanine and isolated cytokine signals only partially activated this phenotype, suggesting that additional soluble factors in the infection microenvironment trigger primary granule release. Findings identify P. aeruginosa as a trigger of acute airway inflammation and neutrophil primary granule exocytosis, underscoring potential roles of airway microbes in prompting this neutrophil subset. Further studies are required to characterize microbes implicated in primary granule release, and identify potential therapeutic targets.
The use of non-bronchoscopic brushings to study the paediatric airway
Publisher: Springer Science and Business Media LLC
Date: 08-06-2005
Abstract: The use of cytology brushes for the purpose of obtaining respiratory cells from adults for clinical and research purposes is well established. However, the safety and utility of non-bronchoscopic brushings to study the paediatric airway has not been assessed. The purpose of this study was to assess the practicality of using non-bronchoscopic brushing to s le epithelial cells from children for investigation of epithelial function in health and disease using a wide range of molecular and cellular techniques. Non-bronchoscopic brushing was investigated in a non-selected cohort of healthy, and mildly asthmatic children presenting for surgery unrelated to respiratory conditions, at the major children's hospital in Perth. Safety and side-effects of the procedure were assessed. Cell number, phenotype and viability were measured for all s les. The potential of these cells for use in long-term cell culture, immunohistochemistry, western blotting, quantitative PCR and gene arraying was examined. Non-bronchoscopic brushing was well tolerated in all children. The only significant side effect following the procedure was cough: nursing staff reported cough in 20% of patients parents reported cough in 40% of patients. Cells s led were of sufficient quantity and quality to allow cell culture in 93% of s les. Similarly, protein and RNA extracted from the cells was suitable for investigation of both gene and protein expression using micro-array and real-time PCR. Non-bronchoscopic brushing in children is safe and easy to perform, and is not associated with any complications. Using this technique, adequate numbers of epithelial cells can be retrieved to allow cell culture, western blotting, real time PCR, and microarray analysis. The purpose of this study is to demonstrate the utility of non-bronchoscopic airway brushing to obtain and study epithelial cells and to encourage others so that we can accelerate our knowledge regarding the role of the epithelium in childhood respiratory disease.
Characterization of Side Population Cells from Human Airway Epithelium
Publisher: Oxford University Press (OUP)
Date: 24-07-2008
DOI: 10.1634/STEMCELLS.2008-0171
Abstract: The airway epithelium is the first line of contact with the inhaled external environment and is continuously exposed to and injured by pollutants, allergens, and viruses. However, little is known about epithelial repair and in particular the identity and role of tissue resident stem rogenitor cells that may contribute to epithelial regeneration. The aims of the present study were to identify, isolate, and characterize side population (SP) cells in human tracheobronchial epithelium. Epithelial cells were obtained from seven nontransplantable healthy lungs and four asthmatic lungs by pronase digestion. SP cells were identified by verapamil-sensitive efflux of the DNA-binding dye Hoechst 33342. Using flow cytometry, CD45− SP, CD45+ SP, and non-SP cells were isolated and sorted. CD45− SP cells made up 0.12% ± 0.01% of the total epithelial cell population in normal airway but 4.1% ± 0.06% of the epithelium in asthmatic airways. All CD45− SP cells showed positive staining for epithelial-specific markers cytokeratin-5, E-cadherin, ZO-1, and p63. CD45− SP cells exhibited stable telomere length and increased colony-forming and proliferative potential, undergoing population expansion for at least 16 consecutive passages. In contrast with non-SP cells, fewer than 100 CD45− SP cells were able to generate a multilayered and differentiated epithelium in air-liquid interface culture. SP cells are present in human tracheobronchial epithelium, exhibit both short- and long-term proliferative potential, and are capable of generation of differentiated epithelium in vitro. The number of SP cells is significantly greater in asthmatic airways, providing evidence of dysregulated resident SP cells in the asthmatic epithelium. Disclosure of potential conflicts of interest is found at the end of this article.
Phage Therapy as an Alternative Treatment Modality for Resistant Staphylococcus aureus Infections
Publisher: MDPI AG
Date: 02-2023
DOI: 10.3390/ANTIBIOTICS12020286
Abstract: The production and use of antibiotics increased significantly after the Second World War due to their effectiveness against bacterial infections. However, bacterial resistance also emerged and has now become an important global issue. Those most in need are typically high-risk and include in iduals who experience burns and other wounds, as well as those with pulmonary infections caused by antibiotic-resistant bacteria, such as Pseudomonas aeruginosa, Acinetobacter sp, and Staphylococci. With investment to develop new antibiotics waning, finding and developing alternative therapeutic strategies to tackle this issue is imperative. One option remerging in popularity is bacteriophage (phage) therapy. This review focuses on Staphylococcus aureus and how it has developed resistance to antibiotics. It also discusses the potential of phage therapy in this setting and its appropriateness in high-risk people, such as those with cystic fibrosis, where it typically forms a biofilm.
Tracing the transmission of mpox through wastewater surveillance in Southeast Asia
Publisher: Oxford University Press (OUP)
Date: 07-2023
DOI: 10.1093/JTM/TAAD096
Abstract: High population density and tourism in Southeast Asia increase the risk of mpox due to frequent interpersonal contacts. Our wastewater surveillance in six Southeast Asian countries revealed positive signals for Monkeypox virus (MPXV) DNA, indicating local transmission. This alerts clinicians and helps allocate resources like testing, vaccines and therapeutics in resource-limited countries.
Previous Influenza Infection Exacerbates Allergen Specific Response and Impairs Airway Barrier Integrity in Pre-Sensitized Mice
Publisher: MDPI AG
Date: 16-08-2021
DOI: 10.3390/IJMS22168790
Abstract: In this study we assessed the effects of antigen exposure in mice pre-sensitized with allergen following viral infection on changes in lung function, cellular responses and tight junction expression. Female BALB/c mice were sensitized to ovalbumin and infected with influenza A before receiving a second ovalbumin sensitization and challenge with saline, ovalbumin (OVA) or house dust mite (HDM). Fifteen days post-infection, bronchoalveolar inflammation, serum antibodies, responsiveness to methacholine and barrier integrity were assessed. There was no effect of infection alone on bronchoalveolar lavage cellular inflammation 15 days post-infection however, OVA or HDM challenge resulted in increased bronchoalveolar inflammation dominated by eosinophils/neutrophils or neutrophils, respectively. Previously infected mice had higher serum OVA-specific IgE compared with uninfected mice. Mice previously infected, sensitized and challenged with OVA were most responsive to methacholine with respect to airway resistance, while HDM challenge caused significant increases in both tissue d ing and tissue elastance regardless of previous infection status. Previous influenza infection was associated with decreased claudin-1 expression in all groups and decreased occludin expression in OVA or HDM-challenged mice. This study demonstrates the importance of the respiratory epithelium in pre-sensitized in iduals, where influenza-infection-induced barrier disruption resulted in increased systemic OVA sensitization and downstream effects on lung function.
The Role of Subinhibitory Concentrations of Daptomycin and Tigecycline in Modulating Virulence in Staphylococcus aureus
Publisher: MDPI AG
Date: 03-01-2021
DOI: 10.3390/ANTIBIOTICS10010039
Abstract: Staphylococcus aureus (S. aureus) infections are notoriously complicated by the ability of the organism to grow in biofilms and are difficult to eradicate with antimicrobial therapy. The purpose of the current study was to clarify the influence of sub-inhibitory concentrations (sub-MICs) of daptomycin and tigecycline antibiotics on biofilm adhesion factors and exoproteins expressions by S. aureus clinical isolates. Six clinical isolates representing positive biofilm S. aureus clones (3 methicillin-sensitive S. aureus (MSSA) and 3 methicillin-resistant S. aureus (MRSA)) were grown with sub-MICs (0.5 MIC) of two antibiotics (daptomycin and tigecycline) for 12 h of incubation. RNA extracted from culture pellets was used via relative quantitative real-time-PCR (qRT-PCR) to determine expression of specific adhesion (fnbA, fnbB, clfA, clfB, fib, ebps, cna, eno) and biofilm (icaADBC) genes. To examine the effect of sub-MIC of these antibiotics on the expression of extracellular proteins, s les from the culture supernatants of six isolates were collected after 12 h of treatment with or without tigecycline in order to profile protein production via 2D gel sodium dodecyl sulfate-polyacrylamide gel electrophoresis (2D gel-SDS-PAGE). Sub-MIC treatment of all clinical MRSA and MSSA strains with daptomycin or tigecycline dramatically induced or suppressed fnbA, fnbB, clfA, clfB, fib, ebps, cna, eno, and icaADBC gene expression. Furthermore, sub-MIC use of tigecycline significantly reduced the total number of separated protein spots across all the isolates, as well as decreasing production of certain in idual proteins. Collectively, this study showed very different responses in terms of both gene expression and protein secretion across the various isolates. In addition, our results suggest that sub-MIC usage of daptomycin and tigecycline could signal virulence induction by S. aureus via the regulation of biofilm adhesion factor genes and exoproteins. If translating findings to the clinical treatment of S. aureus, the therapeutic regimen should be adapted depending on antibiotic, the virulence factor and strain type.
Development and validation of a miniaturized host range screening assay for bacteriophages
Publisher: Cold Spring Harbor Laboratory
Date: 19-02-2021
DOI: 10.1101/2021.02.18.431904
Abstract: Antimicrobial resistance is a global health crisis, partly contributed by inappropriate use of antibiotics. The increasing emergence of multidrug resistant infections has led to the resurgent interest in bacteriophages as an alternative treatment. Current procedures assessing susceptibility and breadth of host range to bacteriophage are conducted using large-scale manual processes that are labor-intensive. The aim here was to establish and validate a scaled down methodology for high-throughput screening in order to reduce procedural footprint. Bacteriophages were isolated from wastewater s les and screened for specificity against 29 clinical Pseudomonas aeruginosa isolates and PA01 using a spot test (2 μL/ drop). Host range assessment was performed on four representative P. aeruginosa isolates using both double agar overlay assay on petri dishes and 24-well culture plates. The breadth of host range of bacteriophages that exhibited lytic activity on P. aeruginosa isolates were corroborated between the current standard practice of whole plate phage assay and 24-well phage assay. The high correlation achieved in this study confirms miniaturization as the first step in future automation that could test phage ersity and efficacy as antimicrobials.
The genetic and epigenetic landscapes of the epithelium in asthma
Publisher: Springer Science and Business Media LLC
Date: 22-09-2016
Nasal airway epithelial repair after very preterm birth
Publisher: European Respiratory Society (ERS)
Date: 04-2021
Suppression of adrenomedullin contributes to vascular leakage and altered epithelial repair during asthma.
Publisher: Wiley
Date: 12-06-2012
DOI: 10.1111/J.1398-9995.2012.02851.X
Abstract: The anti-inflammatory peptide, adrenomedullin (AM), and its cognate receptor are expressed in lung tissue, but its pathophysiological significance in airway inflammation is unknown. This study investigated whether allergen-induced airway inflammation involves an impaired local AM response. Airway AM expression was measured in acute and chronically sensitized mice following allergen inhalation and in airway epithelial cells of asthmatic and nonasthmatic patients. The effects of AM on experimental allergen-induced airway inflammation and of AM on lung epithelial repair in vitro were investigated. Adrenomedullin mRNA levels were significantly (P < 0.05) reduced in acute ovalbumin (OVA)-sensitized mice after OVA challenge, by over 60% at 24 h and for up to 6 days. Similarly, reduced AM expression was observed in two models of chronic allergen-induced inflammation, OVA- and house dust mite-sensitized mice. The reduced AM expression was restricted to airway epithelial and endothelial cells, while AM expression in alveolar macrophages was unaltered. Intranasal AM completely attenuated the OVA-induced airway hyperresponsiveness and mucosal plasma leakage but had no effect on inflammatory cells or cytokines. The effects of inhaled AM were reversed by pre-inhalation of the putative AM receptor antagonist, AM ((22-52)) . AM mRNA levels were significantly (P < 0.05) lower in human asthmatic airway epithelial s les than in nonasthmatic controls. In vitro, AM dose-dependently (10(-11) -10(-7) M) accelerated experimental wound healing in human and mouse lung epithelial cell monolayers and stimulated epithelial cell migration. Adrenomedullin suppression in T(H) 2-related inflammation is of pathophysiological significance and represents loss of a factor that maintains tissue integrity during inflammation.
Comparison of techniques for obtaining lower airway epithelial cells from children
Publisher: European Respiratory Society (ERS)
Date: 09-2008
DOI: 10.1183/09031936.00162507
Abstract: Airway epithelial cells (AECs) are important in asthma as they are the first cells to encounter pathogens/allergens. In children, AECs can be obtained using a "blind" nonbronchoscopic technique through an endotracheal tube. However, due to the increasing use of laryngeal masks the number of children in whom this technique is applicable has become limited. Recently, the present authors began to use a portable "bronchoscope-directed" technique to s le AECs. The current study compares both techniques in both asthmatic and nonasthmatic children. A total of 81 children undergoing elective surgery, were grouped according to atopic status and respiratory symptoms. Cellular yield of blind and bronchoscope-directed brushings were compared and immunocytochemistry performed. AECs were cultured and cytokine analysis of culture supernatant undertaken. Both techniques were equally well-tolerated, with the only adverse effect being a cough in 10% of the subjects. The mean+/-SD cell yield was higher in bronchoscope-directed than blind brushings (5.1+/-2.4 versus 3.1+/-1.4x10(6) cells). Immunocytochemistry confirmed an epithelial cell lineage. Culture supernatant cytokine concentrations were similar regardless of s ling technique with patterns preserved between asthmatic and healthy nonatopic phenotypes. Compared with blind brushing portable bronchoscope-directed brushing is well-tolerated, yields significantly more cells and is a potentially quick and useful technique for obtaining airway epithelial cells for research into childhood respiratory disease, specifically asthma.
The potential of phage therapy in cystic fibrosis: Essential human-bacterial-phage interactions and delivery considerations for use in Pseudomonas aeruginosa-infected airways
Publisher: Elsevier BV
Date: 11-2017
DOI: 10.1016/J.JCF.2017.06.012
Abstract: As antimicrobial-resistant microbes become increasingly common and a significant global issue, novel approaches to treating these infections particularly in those at high risk are required. This is evident in people with cystic fibrosis (CF), who suffer from chronic airway infection caused by antibiotic resistant bacteria, typically Pseudomonas aeruginosa. One option is bacteriophage (phage) therapy, which utilises the natural predation of phage viruses upon their host bacteria. This review summarises the essential and unique aspects of the phage-microbe-human lung interactions in CF that must be addressed to successfully develop and deliver phage to CF airways. The current evidence regarding phage biology, phage-bacterial interactions, potential airway immune responses to phages, previous use of phages in humans and method of phage delivery to the lung are also summarised.
Conditionally reprogrammed primary airway epithelial cells maintain morphology, lineage and disease specific functional characteristics
Publisher: Springer Science and Business Media LLC
Date: 21-12-2017
DOI: 10.1038/S41598-017-17952-4
Abstract: Current limitations to primary cell expansion led us to test whether airway epithelial cells derived from healthy children and those with asthma and cystic fibrosis (CF), co-cultured with an irradiated fibroblast feeder cell in F-medium containing 10 µM ROCK inhibitor could maintain their lineage during expansion and whether this is influenced by underlying disease status. Here, we show that conditionally reprogrammed airway epithelial cells (CRAECs) can be established from both healthy and diseased phenotypes. CRAECs can be expanded, cryopreserved and maintain phenotypes over at least 5 passages. Population doublings of CRAEC cultures were significantly greater than standard cultures, but maintained their lineage characteristics. CRAECs from all phenotypes were also capable of fully differentiating at air-liquid interface (ALI) and maintained disease specific characteristics including defective CFTR channel function cultures and the inability to repair wounds. Our findings indicate that CRAECs derived from children maintain lineage, phenotypic and importantly disease-specific functional characteristics over a specified passage range.
High prevalence of mgrB-mediated colistin resistance among carbapenem-resistant Klebsiella pneumoniae is associated with biofilm formation, and can be overcome by colistin-EDTA combination therapy
Publisher: Springer Science and Business Media LLC
Date: 28-07-2022
DOI: 10.1038/S41598-022-17083-5
Abstract: The global prevalence of colistin-resistant Klebsiella pneumoniae (ColRkp) facilitated by chromosomal and plasmid-mediated Ara4N or PEtN-remodeled LPS alterations has steadily increased with increased colistin usage for treating carbapenem-resistant K. pneumoniae (CRkp). Our study demonstrated the rising trend of ColRkp showing extensively and pandrug-resistant characteristics among CRkp, with a prevalence of 28.5%, which was mediated by chromosomal mgrB , pmrB, or phoQ mutations (91.5%), and plasmid-mediated mcr-1.1, mcr-8.1, mcr-8.2 alone or in conjunction with R256G PmrB (8.5%). Several genetic alterations in mgrB (85.1%) with increased expressions of Ara4N-related phoPQ and pmrK were critical for establishing colistin resistance in our isolates. In this study, we discovered the significant associations between extensively drug-resistant bacteria (XDR) and pandrug-resistant bacteria (PDR) ColRkp in terms of moderate, weak or no biofilm-producing abilities, and altered expressions of virulence factors. These ColRkp would therefore be very challenging to treat, emphasizing for innovative therapy to combat these infections. Regardless of the underlying colistin-resistant mechanisms, colistin-EDTA combination therapy in this study produced potent synergistic effects in both in vitro and in vivo murine bacteremia, with no ColRkp regrowth and improved animal survival, implying the significance of colistin-EDTA combination therapy as systemic therapy for unlocking colistin resistance in ColRkp-associated bacteremia.
Primary Nasal Epithelial Cells As a Type-II Alveolar Surrogate Cell Culture Model for ABCA-3 Deficiency
Publisher: Research Square Platform LLC
Date: 08-09-2021
DOI: 10.21203/RS.3.RS-860700/V1
Abstract: ATP Binding Cassette Subfamily A Member 3 (ABCA-3) is a lipid transporter protein highly expressed in type-II alveolar (AT-II) cells. Mutations in ABCA3 can result in severe respiratory disease in infants and children. To study ABCA-3 deficiency in vitro , primary AT-II cells would be the cell culture of choice although s le accessibility is limited. Our aim was to investigate the suitability of primary nasal epithelial cells, as a surrogate culture model for AT-II cells, to study ABCA-3 deficiency. Expression of ABCA3 , and surfactant protein genes, SFTPB and SFTPC , was detected in primary nasal epithelial cells but at a significantly lower level than in AT-II cells. ABCA-3, SP-B and SP-C were detected by immunofluorescence microscopy in primary nasal epithelial cells. However, SP-B and SP-C were undetectable in primary nasal epithelial cells using western blot. Structurally imperfect lamellar bodies were observed in primary nasal epithelial cells using transmission electron microscopy. Functional assessment of the ABCA-3 protein demonstrated that higher concentrations of doxorubicin reduced cell viability in ABCA-3 deficient nasal epithelial cells compared to controls in an assay-dependent manner. Our results indicate that there may be a role for primary nasal epithelial cell cultures to model ABCA-3 deficiency in vitro although additional cell culture models that more effectively recapitulate the AT-II phenotype may be required.
Rhinovirus exacerbates house-dust-mite induced lung disease in adult mice
Publisher: Public Library of Science (PLoS)
Date: 14-03-2014
Living with lung disease: experimental models to assess the long-term effects of prematurity
Publisher: American Physiological Society
Date: 11-2022
DOI: 10.1152/AJPLUNG.00155.2022
Abstract: Laboratory models provide an important tool in helping to understand the cellular and molecular drivers of respiratory disease. Many animal models exist that model the neonatal outcomes of preterm birth. Discoveries at the laboratory bench from examination of both human tissue and tissues from animal models have informed the life-saving technologies and clinical care used today. Yet animal laboratory models of preterm birth have rarely been utilized beyond the neonatal period, despite growing reports of respiratory symptoms and subnormal lung function throughout childhood. Elucidation of the driving factors and physiological explanations underpinning poor outcomes in survivors of preterm birth are crucial to optimize clinical care and identify therapeutic targets. Can existing neonatal models be utilized to study respiratory outcomes beyond infancy? This review answers the question by highlighting the clinical evidence underpinning an active respiratory disease process after preterm birth and exploring the benefits and drawbacks of existing models to conduct research into the long-term respiratory outcomes of preterm birth.
Biodiesel exhaust-induced cytotoxicity and proinflammatory mediator production in human airway epithelial cells.
Publisher: Wiley
Date: 05-07-2014
DOI: 10.1002/TOX.22020
Abstract: Increasing use of biodiesel has prompted research into the potential health effects of biodiesel exhaust exposure. Few studies directly compare the health consequences of mineral diesel, biodiesel, or blend exhaust exposures. Here, we exposed human epithelial cell cultures to diluted exhaust generated by the combustion of Australian ultralow-sulfur-diesel (ULSD), unprocessed canola oil, 100% canola biodiesel (B100), and a blend of 20% canola biodiesel mixed with 80% ULSD. The physicochemical characteristics of the exhaust were assessed and we compared cellular viability, apoptosis, and levels of interleukin (IL)-6, IL-8, and Regulated on Activation, Normal T cell Expressed and Secreted (RANTES) in exposed cultured cells. Different fuel types produced significantly different amounts of exhaust gases and different particle characteristics. All exposures resulted in significant apoptosis and loss of viability when compared with control, with an increasing proportion of biodiesel being correlated with a decrease in viability. In most cases, exposure to exhaust resulted in an increase in mediator production, with the greatest increases most often in response to B100. Exposure to pure canola oil (PCO) exhaust did not increase mediator production, but resulted in a significant decrease in IL-8 and RANTES in some cases. Our results show that canola biodiesel exhaust exposure elicits inflammation and reduces viability of human epithelial cell cultures in vitro when compared with ULSD exhaust exposure. This may be related to an increase in particle surface area and number in B100 exhaust when compared with ULSD exhaust. Exposure to PCO exhaust elicited the greatest loss of cellular viability, but virtually no inflammatory response, likely due to an overall increase in average particle size.
Effects of human rhinovirus on epithelial barrier integrity and function in children with asthma.
Publisher: Wiley
Date: 20-02-2018
DOI: 10.1111/CEA.13097
Abstract: Bronchial epithelial tight junctions (TJ) have been extensively assessed in healthy airway epithelium. However, no studies have yet assessed the effect of human rhinovirus (HRV) infection on the expression and resultant barrier function in epithelial tight junctions (TJ) in childhood asthma. To investigate the impact of HRV infection on airway epithelial TJ expression and barrier function in airway epithelial cells (AECs) of children with and without asthma. Furthermore, to test the hypothesis that barrier integrity and function is compromised to a greater extent by HRV in AECs from asthmatic children. Primary AECs were obtained from children with and without asthma, differentiated into air-liquid interface (ALI) cultures and infected with rhinovirus. Expression of claudin-1, occludin and zonula occluden-1 (ZO-1) was assessed via qPCR, immunocytochemistry (ICC), in-cell western (ICW) and confocal microscopy. Barrier function was assessed by transepithelial electrical resistance (TER R Basal TJ gene expression of claudin-1 and occludin was significantly upregulated in asthmatic children compared to non-asthmatics however, no difference was seen with ZO-1. Interestingly, claudin-1, occludin and ZO-1 protein expression was significantly reduced in AEC of asthmatic children compared to non-asthmatic controls suggesting possible post-transcriptional inherent differences. HRV infection resulted in a transient dissociation of TJ and airway barrier integrity in non-asthmatic children. Although similar dissociation of TJ was observed in asthmatic children, a significant and sustained reduction in TJ expression concurrent with both a significant decrease in TER and an increase in permeability in asthmatic children was observed. This study demonstrates novel intrinsic differences in TJ gene and protein expression between AEC of children with and without asthma. Furthermore, it correlates directly the relationship between HRV infection and the resultant dissociation of epithelial TJ that causes a continued altered barrier function in children with asthma.
Airway surface liquid pH is not acidic in children with cystic fibrosis
Publisher: Springer Science and Business Media LLC
Date: 08-2017
DOI: 10.1038/S41467-017-00532-5
Abstract: Modulation of airway surface liquid (ASL) pH has been proposed as a therapy for cystic fibrosis (CF). However, evidence that ASL pH is reduced in CF is limited and conflicting. The technical challenges associated with measuring ASL pH in vivo have precluded accurate measurements in humans. In order to address this deficiency, ASL pH was measured in vivo in children using a novel luminescent technology integrated with fibre-optic probes. Here we show that ASL pH in children with CF is similar to that of children without CF. Findings were supported by highly controlled direct pH measurements in primary human airway epithelial cell culture models, which also suggest that the potential ASL pH gradient produced by defective apical ion transport is balanced out by paracellular shunting of acid/base. Thus, reduced baseline ASL pH is unlikely to be an important pathobiological factor in early CF lung disease.
Of pigs, mice, and men: Understanding early triggers of cystic fibrosis lung disease
Publisher: American Thoracic Society
Date: 10-2016
Multiple traces of monkeypox detected in non-sewered wastewater with sparse sampling from a densely populated metropolitan area in Asia
Publisher: Elsevier BV
Date: 02-2023
Hypoxia and sterile inflammation in cystic fibrosis airways: Mechanisms and potential therapies
Publisher: European Respiratory Society (ERS)
Date: 23-12-2017
DOI: 10.1183/13993003.00903-2016
Abstract: Cystic fibrosis is one of the most common autosomal recessive genetic diseases in Caucasian populations. Diagnosis via newborn screening and targeted nutritional and antibiotic therapy have improved outcomes, however respiratory failure remains the key cause of morbidity and mortality. Progressive respiratory disease in cystic fibrosis is characterised by chronic neutrophilic airway inflammation associated with structural airway damage leading to bronchiectasis and decreased lung function. Mucus obstruction is a characteristic early abnormality in the cystic fibrosis airway, associated with neutrophilic inflammation often in the absence of detectable infection. Recent studies have suggested a link between hypoxic cell death and sterile neutrophilic inflammation in cystic fibrosis and other diseases via the IL-1 signalling pathway. In this review, we consider recent evidence regarding the cellular responses to respiratory hypoxia as a potential driver of sterile neutrophilic inflammation in the lung, current knowledge on hypoxia as a pathogenic mechanism in cystic fibrosis and the potential for current and future therapies to alleviate hypoxia-driven sterile inflammation.
Cystic Fibrosis Clinical Isolates of Aspergillus fumigatus Induce Similar Muco-inflammatory Responses in Primary Airway Epithelial Cells.
Publisher: MDPI AG
Date: 13-08-2021
DOI: 10.3390/PATHOGENS10081020
Abstract: Aspergillus is increasingly associated with lung inflammation and mucus plugging in early cystic fibrosis (CF) disease during which conidia burden is low and strains appear to be highly erse. It is unknown whether clinical Aspergillus strains vary in their capacity to induce epithelial inflammation and mucus production. We tested the hypothesis that in idual colonising strains of Aspergillus fumigatus would induce different responses. Ten paediatric CF Aspergillus isolates were compared along with two systemically invasive clinical isolates and an ATCC reference strain. Isolates were first characterised by ITS gene sequencing and screened for antifungal susceptibility. Three clusters (A−C) of Aspergillus isolates were identified by ITS. Antifungal susceptibility was variable, particularly for itraconazole. Submerged CF and non-CF monolayers as well as differentiated primary airway epithelial cell cultures were incubated with conidia for 24 h to allow germination. None of the clinical isolates were found to significantly differ from one another in either IL-6 or IL-8 release or gene expression of secretory mucins. Clinical Aspergillus isolates appear to be largely homogenous in their mucostimulatory and immunostimulatory capacities and, therefore, only the antifungal resistance characteristics are likely to be clinically important.
Comment on ''Long-Term Effects of Diesel Exhaust Particles on Airway Inflammation and Remodeling in a Mouse Model by Kim et al.
Publisher: The Korean Academy of Asthma, Allergy and Clinical Immunology and The Korean Academy of Pediatric Al
Date: 2017
The potential of antisense oligonucleotide therapies for inherited childhood lung diseases
Publisher: Springer Science and Business Media LLC
Date: 06-02-2018
Respiratory Health Effects of In Vivo Sub-Chronic Diesel and Biodiesel Exhaust Exposure
Publisher: MDPI AG
Date: 07-03-2023
DOI: 10.3390/IJMS24065130
Abstract: Biodiesel, which can be made from a variety of natural oils, is currently promoted as a sustainable, healthier replacement for commercial mineral diesel despite little experimental data supporting this. The aim of our research was to investigate the health impacts of exposure to exhaust generated by the combustion of diesel and two different biodiesels. Male BALB/c mice (n = 24 per group) were exposed for 2 h/day for 8 days to diluted exhaust from a diesel engine running on ultra-low sulfur diesel (ULSD) or Tallow or Canola biodiesel, with room air exposures used as control. A variety of respiratory-related end-point measurements were assessed, including lung function, responsiveness to methacholine, airway inflammation and cytokine response, and airway morphometry. Exposure to Tallow biodiesel exhaust resulted in the most significant health impacts compared to Air controls, including increased airway hyperresponsiveness and airway inflammation. In contrast, exposure to Canola biodiesel exhaust resulted in fewer negative health effects. Exposure to ULSD resulted in health impacts between those of the two biodiesels. The health effects of biodiesel exhaust exposure vary depending on the feedstock used to make the fuel.
Phage therapy for multi-drug resistant respiratory tract infections
Publisher: MDPI AG
Date: 11-09-2021
DOI: 10.3390/V13091809
Abstract: The emergence of multi-drug resistant (MDR) bacteria is recognised today as one of the greatest challenges to public health. As traditional antimicrobials are becoming ineffective and research into new antibiotics is diminishing, a number of alternative treatments for MDR bacteria have been receiving greater attention. Bacteriophage therapies are being revisited and present a promising opportunity to reduce the burden of bacterial infection in this post-antibiotic era. This review focuses on the current evidence supporting bacteriophage therapy against prevalent or emerging multi-drug resistant bacterial pathogens in respiratory medicine and the challenges ahead in preclinical data generation. Starting with efforts to improve delivery of bacteriophages to the lung surface, the current developments in animal models for relevant efficacy data on respiratory infections are discussed before finishing with a summary of findings from the select human trials performed to date.
Airway epithelial cells secrete altered exosomal microRNAs in murine experimental and human paediatric asthma
Publisher: Georg Thieme Verlag KG
Date: 09-02-2016
Ivacaftor or lumacaftor/ivacaftor treatment does not alter the core CF airway epithelial gene response to rhinovirus
Publisher: Elsevier BV
Date: 2020
DOI: 10.1016/J.JCF.2020.07.004
Abstract: Aberrant responses by the cystic fibrosis airway epithelium during viral infection may underly the clinical observations. Whether CFTR modulators affect antiviral responses by CF epithelia is presently unknown. We tested the hypothesis that treatment of CF epithelial cells with ivacaftor (Iva) or ivacaftor/lumacaftor (Iva/Lum) would improve control of rhinovirus infection. Nineteen CF epithelial cultures (10 homozygous for p.Phe508del as CFTR Class 2, 9 p.Phe508del .Gly551Asp as Class 3) were infected with rhinovirus 1B at multiplicity of infection 12 for 24 h. Culture RNA and supernatants were harvested to assess gene and protein expression respectively. RNA-seq analysis comparing rhinovirus infected cultures to control identified 796 and 629 differentially expressed genes for Class 2 and Class 3, respectively. This gene response was highly conserved when cells were treated with CFTR modulators and were predicted to be driven by the same interferon-pathway transcriptional regulators (IFNA, IFNL1, IFNG, IRF7, STAT1). Direct comparisons between treated and untreated infected cultures did not yield any differentially expressed genes for Class 3 and only 68 genes for Class 2. Changes were predominantly related to regulators of lipid metabolism and inflammation, aspects of epithelial biology known to be dysregulated in CF. In addition, CFTR modulators did not affect viral copy number, or levels of pro-inflammatory cytokines produced post-infection. Though long-term clinical data is not yet available, results presented here suggest that first generation CFTR modulators do not interfere with core airway epithelial responses to rhinovirus infection. Future work should investigate the latest triple modulation therapies.
Successful establishment of primary small airway cell cultures in human lung transplantation
Publisher: Springer Science and Business Media LLC
Date: 26-10-2009
Abstract: The study of small airway diseases such as post-transplant bronchiolitis obliterans syndrome (BOS) is h ered by the difficulty in assessing peripheral airway function either physiologically or directly. Our aims were to develop robust methods for s ling small airway epithelial cells (SAEC) and to establish submerged SAEC cultures for downstream experimentation. SAEC were obtained at 62 post-transplant bronchoscopies in 26 patients using radiologically guided bronchial brushings. Submerged cell cultures were established and SAEC lineage was confirmed using expression of clara cell secretory protein (CCSP). The cell yield for SAEC (0.956 ± 0.063 × 10 6 ) was lower than for large airway cells (1.306 ± 0.077 × 10 6 ) but did not significantly impact on the culture establishment rate (79.0 ± 5.2% vs. 83.8 ± 4.7% p = 0.49). The presence of BOS significantly compromised culture success (independent of cell yield) for SAEC (odds ratio (95%CI) 0.067 (0.01-0.40)) but not LAEC (0.3 (0.05-1.9)). Established cultures were successfully passaged and expanded. Primary SAEC can be successfully obtained from human lung transplant recipients and maintained in culture for downstream experimentation. This technique will facilitate the development of primary in vitro models for BOS and other diseases with a small airway component such as asthma, cystic fibrosis and COPD.
Disruption of β-catenin/CBP signaling inhibits human airway epithelial-mesenchymal transition and repair
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.BIOCEL.2015.08.014
Abstract: The epithelium of asthmatics is characterized by reduced expression of E-cadherin and increased expression of the basal cell markers ck-5 and p63 that is indicative of a relatively undifferentiated repairing epithelium. This phenotype correlates with increased proliferation, compromised wound healing and an enhanced capacity to undergo epithelial-mesenchymal transition (EMT). The transcription factor β-catenin plays a vital role in epithelial cell differentiation and regeneration, depending on the co-factor recruited. Transcriptional programs driven by the β-catenin/CBP axis are critical for maintaining an undifferentiated and proliferative state, whereas the β-catenin 300 axis is associated with cell differentiation. We hypothesized that disrupting the β-catenin/CBP signaling axis would promote epithelial differentiation and inhibit EMT. We treated monolayer cultures of human airway epithelial cells with TGFβ1 in the presence or absence of the selective small molecule ICG-001 to inhibit β-catenin/CBP signaling. We used western blots to assess expression of an EMT signature, CBP, p300, β-catenin, fibronectin and ITGβ1 and scratch wound assays to assess epithelial cell migration. Snai-1 and -2 expressions were determined using q-PCR. Exposure to TGFβ1 induced EMT, characterized by reduced E-cadherin expression with increased expression of α-smooth muscle actin and EDA-fibronectin. Either co-treatment or therapeutic administration of ICG-001 completely inhibited TGFβ1-induced EMT. ICG-001 also reduced the expression of ck-5 and -19 independent of TGFβ1. Exposure to ICG-001 significantly inhibited epithelial cell proliferation and migration, coincident with a down regulation of ITGβ1 and fibronectin expression. These data support our hypothesis that modulating the β-catenin/CBP signaling axis plays a key role in epithelial plasticity and function.
<p>COPD-Related Modification to the Airway Epithelium Permits Intracellular Residence of Nontypeable <em>Haemophilus influenzae</em> and May Be Potentiated by Macrolide Arrest of Aut
Publisher: Informa UK Limited
Date: 06-2020
DOI: 10.2147/COPD.S245819
Persistent activation of interlinked type 2 airway epithelial gene networks in sputum-derived cells from aeroallergen-sensitized symptomatic asthmatics
Publisher: Springer Science and Business Media LLC
Date: 24-01-2018
DOI: 10.1038/S41598-018-19837-6
Abstract: Atopic asthma is a persistent disease characterized by intermittent wheeze and progressive loss of lung function. The disease is thought to be driven primarily by chronic aeroallergen-induced type 2-associated inflammation. However, the vast majority of atopics do not develop asthma despite ongoing aeroallergen exposure, suggesting additional mechanisms operate in conjunction with type 2 immunity to drive asthma pathogenesis. We employed RNA-Seq profiling of sputum-derived cells to identify gene networks operative at baseline in house dust mite-sensitized (HDM S ) subjects with/without wheezing history that are characteristic of the ongoing asthmatic state. The expression of type 2 effectors (IL-5, IL-13) was equivalent in both cohorts of subjects. However, in HDM S -wheezers they were associated with upregulation of two coexpression modules comprising multiple type 2- and epithelial-associated genes. The first module was interlinked by the hubs EGFR, ERBB2, CDH1 and IL-13. The second module was associated with CDHR3 and mucociliary clearance genes. Our findings provide new insight into the molecular mechanisms operative at baseline in the airway mucosa in atopic asthmatics undergoing natural aeroallergen exposure, and suggest that susceptibility to asthma amongst these subjects involves complex interactions between type 2- and epithelial-associated gene networks, which are not operative in equivalently sensitized/exposed atopic non-asthmatics.
Identification of Epithelial Phospholipase A2 Receptor 1 as a Potential Target in Asthma
Publisher: American Thoracic Society
Date: 12-2016
Pulmonary bacteriophage and cystic fibrosis airway mucus: friends or foes?
Publisher: Frontiers Media SA
Date: 17-05-2023
DOI: 10.3389/FMED.2023.1088494
Abstract: For those born with cystic fibrosis (CF), hyper-concentrated mucus with a dysfunctional structure significantly impacts CF airways, providing a perfect environment for bacterial colonization and subsequent chronic infection. Early treatment with antibiotics limits the prevalence of bacterial pathogens but permanently alters the CF airway microenvironment, resulting in antibiotic resistance and other long-term consequences. With little investment into new traditional antibiotics, safe and effective alternative therapeutic options are urgently needed. One gathering significant traction is bacteriophage (phage) therapy. However, little is known about which phages are effective for respiratory infections, the dynamics involved between phage(s) and the host airway, and associated by-products, including mucus. Work utilizing gut cell models suggest that phages adhere to mucus components, reducing microbial colonization and providing non-host-derived immune protection. Thus, phages retained in the CF mucus layer result from the positive selection that enables them to remain in the mucus layer. Phages bind weakly to mucus components, slowing down the diffusion motion and increasing their chance of encountering bacterial species for subsequent infection. Adherence of phage to mucus could also facilitate phage enrichment and persistence within the microenvironment, resulting in a potent phage phenotype or vice versa. However, how the CF microenvironment responds to phage and impacts phage functionality remains unknown. This review discusses CF associated lung diseases, the impact of CF mucus, and chronic bacterial infection. It then discusses the therapeutic potential of phages, their dynamic relationship with mucus and whether this may enhance or hinder airway bacterial infections in CF.
Azithromycin Partially Mitigates Dysregulated Repair of Lung Allograft Small Airway Epithelium.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2020
Persistent induction of goblet cell differentiation in the airways: Therapeutic approaches
Publisher: Elsevier BV
Date: 05-2018
DOI: 10.1016/J.PHARMTHERA.2017.12.009
Abstract: Dysregulated induction of goblet cell differentiation results in excessive production and retention of mucus and is a common feature of several chronic airways diseases. To date, therapeutic strategies to reduce mucus accumulation have focused primarily on altering the properties of the mucus itself, or have aimed to limit the production of mucus-stimulating cytokines. Here we review the current knowledge of key molecular pathways that are dysregulated during persistent goblet cell differentiation and highlights both pre-existing and novel therapeutic strategies to combat this pathology.
Transcriptomic analyses reveal regional signatures in lung allograft recipients
Publisher: Cold Spring Harbor Laboratory
Date: 03-04-2023
DOI: 10.1101/2023.04.03.23288063
Abstract: Long term outcomes of allograft recipients are compromised by the development of chronic lung allograft dysfunction (CLAD) promoting bronchiolitis obliterans syndrome (BOS). We established baseline transcriptomic profiles of both the large and small airway epithelial cells (referred as LAEC and SAEC, respectively) to identify regional differences irrespective of initiating disease. We obtained matched primary LAEC and SAEC from lung allograft recipients (n=4, 42.5 ± 4.2 years) and established primary cultures. Bulk RNA sequencing was performed to determine differentially expressed genes. We observed differences in the transcriptional program between LAEC and SAEC Transcription factors (TF) were ranked within the top ten differentially regulated genes. The most abundant TF families included C2H2-ZF, homeobox and bHLH. Upstream regulator analyses identified homeobox genes being significantly in LAEC. Protein-protein interaction network analysis emphasised the role of TFs ( ISL1, MSX1, HOXA1, GATA6, ZNF423 ) in airway modulation. Additionally, functional enrichment analysis revealed the activation of chemotaxis, metalloendipeptidase/metallopeptidase activity and pro-inflammatory signatures (IL17 signalling and RAGE), in LAEC, while SAEC were characterised by elevated expression of surfactant metabolism related genes. Moreover, alveolar and club cells-related genes were expressed in SAEC, suggesting a lower airway-specific signature. Our analysis shows robust transcriptional differences between LAEC and SAEC. We suggest a potential role for homeobox TF family as well as the activation of the immune system in the biology of LAEC. Conversely, we observed an alveoli-like transcriptional signature in SAEC, including gas-exchange signals and surfactant metabolism pathways involved in lung homeostasis.
Regional Differences in Susceptibiity of Bronchial Epithelium to Mesenchymal Transition and Inhibition by the Macrolide Antibiotic Azithromycin
Publisher: Public Library of Science (PLoS)
Date: 21-12-2012
In Vitro primary human airway epithelial whole exhaust exposure.
Publisher: Elsevier BV
Date: 2021
Selection of housekeeping genes for real-time PCR in atopic human bronchial epithelial cells
Publisher: European Respiratory Society (ERS)
Date: 09-2008
DOI: 10.1183/09031936.00129107
Abstract: The stability of housekeeping genes (HKGs) is critical when performing real-time quantitative PCR. To date, the stability of common HKGs has not been systematically compared in human airway epithelial cells (AEC) in normal and atopic subjects. Expression levels of 12 HKGs were measured in AECs from a cohort of 30 healthy atopic nonasthmatic or atopic asthmatic children. Gene expression stability was determined using three different Visual Basic for Applications applets (geNorm, NormFinder and BestKeeper). All 12 HKGs were expressed in AECs. However, the hypoxanthine ribosyltransferase and TATA-binding protein genes were excluded from further analysis due to low expression levels. The cyclophilin A gene was ranked the most stable by all three methods. The expression levels of the beta-actin and glyceraldehyde-3-phosphate dehydrogenase genes were significantly different between the three groups of patients, with atopic asthmatics showing the highest expression levels for both genes. The results suggest that the cyclophilin A gene is the most suitable housekeeping gene analysed for expression studies utilising uncultured bronchial airway epithelial cells from healthy and asthmatic children, and highlight the importance of validating housekeeping genes for each experimental model.
Pulmonary microRNA profiles identify involvement of Creb1 and Sec14l3 in bronchial epithelial changes in allergic asthma
Publisher: Springer Science and Business Media LLC
Date: 06-04-2017
DOI: 10.1038/SREP46026
Abstract: Asthma is highly prevalent, but current therapies cannot influence the chronic course of the disease. It is thus important to understand underlying early molecular events. In this study, we aimed to use microRNAs (miRNAs) - which are critical regulators of signaling cascades - to identify so far uncharacterized asthma pathogenesis pathways. Therefore, deregulation of miRNAs was assessed in whole lungs from mice with ovalbumin (OVA)-induced allergic airway inflammation (AAI). In silico predicted target genes were confirmed in reporter assays and in house-dust-mite (HDM) induced AAI and primary human bronchial epithelial cells (NHBE) cultured at the air-liquid interface. We identified and validated the transcription factor cAMP-responsive element binding protein (Creb1) and its transcriptional co-activators (Crtc1-3) as targets of miR-17, miR-144, and miR-21. Sec14-like 3 (Sec14l3) - a putative target of Creb1 - was down-regulated in both asthma models and in NHBE cells upon IL13 treatment, while it’s expression correlated with ciliated cell development and decreased along with increasing goblet cell metaplasia. Finally, we propose that Creb1/Crtc1-3 and Sec14l3 could be important for early responses of the bronchial epithelium to Th2-stimuli. This study shows that miRNA profiles can be used to identify novel targets that would be overlooked in mRNA based strategies.
Ancestral SARS-CoV-2, but not Omicron, replicates less efficiently in primary pediatric nasal epithelial cells
Publisher: Public Library of Science (PLoS)
Date: 08-2022
DOI: 10.1371/JOURNAL.PBIO.3001728
Abstract: Children typically experience more mild symptoms of Coronavirus Disease 2019 (COVID-19) when compared to adults. There is a strong body of evidence that children are also less susceptible to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection with the ancestral viral isolate. However, the emergence of SARS-CoV-2 variants of concern (VOCs) has been associated with an increased number of pediatric infections. Whether this is the result of widespread adult vaccination or fundamental changes in the biology of SARS-CoV-2 remain to be determined. Here, we use primary nasal epithelial cells (NECs) from children and adults, differentiated at an air–liquid interface to show that the ancestral SARS-CoV-2 replicates to significantly lower titers in the NECs of children compared to those of adults. This was associated with a heightened antiviral response to SARS-CoV-2 in the NECs of children. Importantly, the Delta variant also replicated to significantly lower titers in the NECs of children. This trend was markedly less pronounced in the case of Omicron. It is also striking to note that, at least in terms of viral RNA, Omicron replicated better in pediatric NECs compared to both Delta and the ancestral virus. Taken together, these data show that the nasal epithelium of children supports lower infection and replication of ancestral SARS-CoV-2, although this may be changing as the virus evolves.
Cells of Epithelial Lineage Are Present in Blood, Engraft the Bronchial Epithelium, and Are Increased in Human Lung Transplantation
Publisher: Elsevier BV
Date: 06-2009
DOI: 10.1016/J.HEALUN.2009.03.013
Abstract: There is a growing expectation that cell-based therapies will prove effective for a wide range of conditions including lung diseases such as cystic fibrosis. The promise of these therapies will depend largely on effective delivery and engraftment. In this study, in the setting of human lung transplantation, we sought to determine whether exogenous epithelial cells are able to engraft the transplanted organ and if cells of a similar phenotype could be detected in peripheral blood. Cells obtained from bronchial brushings and peripheral blood were analyzed via dual fluorescent in situ hybridization/fluorescent immunohistochemistry (FISH/IHC), short tandem repeat polymerase chain reaction (STR-PCR) and flow cytometry. In 2 of 3 gender-mismatched patients we observed limited (5.9% to 6.8% by STR-PCR and 3.5% to 4% by FISH/IHC) engraftment of the bronchial epithelium by exogenous epithelial cells. Engrafting cells were CD34(-) CD15(-) CD68(-) c-Kit(-), but expressed CXCR4 on the cell surface. Cells with a similar phenotype were also identified in peripheral blood. In 8 patients, at 2 to 66 months post-transplant, 0.57 +/- 0.17% of CD14(-) peripheral blood mononuclear cells were of epithelial lineage. Almost all were CD45(+) and most expressed CXCR4 on the cell membrane. Cells of epithelial lineage were also identified in peripheral blood in healthy in iduals but in much lower numbers (0.08 +/- 0.01%, p < 0.05). Cells of epithelial lineage are detectable in peripheral blood and are able to engraft the bronchial epithelium in humans. Cell numbers are increased in lung transplantation.
The AREST CF experience in biobanking - More than just tissues, tubes and time
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.JCF.2017.08.003
Abstract: Research to further improve outcomes for people with CF is dependent upon well characterised, archived and accessible clinical specimens. The recent article by Beekman et al. published in Journal of Cystic Fibrosis summarised a scientific meeting at the 13th ECFS Basic Science Conference. This meeting discussed how well-annotated, clinical biobanks for CF could be established in Europe to meet the needs of therapeutic development. The Australian Respiratory Early Surveillance Team for Cystic Fibrosis (AREST CF) has conducted biobanking of CF research and clinical specimens since the late 1990s and is custodian of the most comprehensive paediatric CF biobank in the world that focuses on the first years of life. This short communication will describe the approach undertaken by AREST CF in establishing a clinical specimen biobank.
Decreased fibronectin production significantly contributes to dysregulated repair of asthmatic epithelium
Publisher: American Thoracic Society
Date: 05-2010
SEC14-like 3 is decreased in airway ciliated cells in experimental and paediatric asthma
Publisher: Georg Thieme Verlag KG
Date: 08-04-2015
Visualisation of Multiple Tight Junctional Complexes in Human Airway Epithelial Cells.
Publisher: Springer Science and Business Media LLC
Date: 02-2018
Identification of genes differentially regulated by vitamin D deficiency that alter lung pathophysiology and inflammation in allergic airways disease
Publisher: American Physiological Society
Date: 09-2016
DOI: 10.1152/AJPLUNG.00026.2016
Abstract: Vitamin D deficiency is associated with asthma risk. Vitamin D deficiency may enhance the inflammatory response, and we have previously shown that airway remodeling and airway hyperresponsiveness is increased in vitamin D-deficient mice. In this study, we hypothesize that vitamin D deficiency would exacerbate house dust mite (HDM)-induced inflammation and alterations in lung structure and function. A BALB/c mouse model of vitamin D deficiency was established by dietary manipulation. Responsiveness to methacholine, airway smooth muscle (ASM) mass, mucus cell metaplasia, lung and airway inflammation, and cytokines in bronchoalveolar lavage (BAL) fluid were assessed. Gene expression patterns in mouse lung s les were profiled by RNA-Seq. HDM exposure increased inflammation and inflammatory cytokines in BAL, baseline airway resistance, tissue elastance, and ASM mass. Vitamin D deficiency enhanced the HDM-induced influx of lymphocytes into BAL, ameliorated the HDM-induced increase in ASM mass, and protected against the HDM-induced increase in baseline airway resistance. RNA-Seq identified nine genes that were differentially regulated by vitamin D deficiency in the lungs of HDM-treated mice. Immunohistochemical staining confirmed that protein expression of midline 1 (MID1) and adrenomedullin was differentially regulated such that they promoted inflammation, while hypoxia-inducible lipid droplet-associated, which is associated with ASM remodeling, was downregulated. Protein expression studies in human bronchial epithelial cells also showed that addition of vitamin D decreased MID1 expression. Differential regulation of these genes by vitamin D deficiency could determine lung inflammation and pathophysiology and suggest that the effect of vitamin D deficiency on HDM-induced allergic airways disease is complex.
Productive infection of human embryonic stem cell-derived NKX2.1+ respiratory progenitors with human rhinovirus
Publisher: Oxford University Press (OUP)
Date: 14-04-2015
Abstract: This report provides proof-of-principle experiments demonstrating, for the first time, that human respiratory progenitor cells derived from stem cells in the laboratory can be productively infected with human rhinovirus, the predominant cause of the common cold.
Update on SLC6A14 in lung and gastrointestinal physiology and physiopathology: focus on cystic fibrosis
Publisher: Springer Science and Business Media LLC
Date: 12-03-2020
DOI: 10.1007/S00018-020-03487-X
Abstract: The solute carrier family 6 member 14 (SLC6A14) protein imports and concentrates all neutral amino acids as well as the two cationic acids lysine and arginine into the cytoplasm of different cell types. Primarily described as involved in several cancer and colonic diseases physiopathological mechanisms, the SLC6A14 gene has been more recently identified as a genetic modifier of cystic fibrosis (CF) disease severity. It was indeed shown to have a pleiotropic effect, modulating meconium ileus occurrence, lung disease severity, and precocity of P. aeruginosa airway infection. The biological mechanisms explaining the impact of SLC6A14 on intestinal and lung phenotypes of CF patients are starting to be elucidated. This review focuses on SLC6A14 in lung and gastrointestinal physiology and physiopathology, especially its involvement in the pathophysiology of CF disease.
Assessment of p.Phe508del-CFTR functional restoration in pediatric primary cystic fibrosis airway epithelial cells
Publisher: Public Library of Science (PLoS)
Date: 23-01-2018
Bacteriophage
Publisher: Frontiers Media SA
Date: 14-12-2022
DOI: 10.3389/FMED.2022.1069929
Abstract: Persistent respiratory bacterial infections are a clinical burden in several chronic inflammatory airway diseases and are often associated with neutrophil infiltration into the lungs. Following recruitment, dysregulated neutrophil effector functions such as increased granule release and formation of neutrophil extracellular traps (NETs) result in damage to airway tissue, contributing to the progression of lung disease. Bacterial pathogens are a major driver of airway neutrophilic inflammation, but traditional management of infections with antibiotic therapy is becoming less effective as rates of antimicrobial resistance rise. Bacteriophages (phages) are now frequently identified as antimicrobial alternatives for antimicrobial resistant (AMR) airway infections. Despite growing recognition of their bactericidal function, less is known about how phages influence activity of neutrophils recruited to sites of bacterial infection in the lungs. In this review, we summarize current in vitro and in vivo findings on the effects of phage therapy on neutrophils and their inflammatory mediators, as well as mechanisms of phage-neutrophil interactions. Understanding these effects provides further validation of their safe use in humans, but also identifies phages as a targeted neutrophil-modulating therapeutic for inflammatory airway conditions.
Airway Epithelium Respiratory Illnesses and Allergy (AERIAL) birth cohort: study protocol
Publisher: Cold Spring Harbor Laboratory
Date: 03-05-2023
DOI: 10.1101/2023.04.29.23289314
Abstract: Recurrent wheezing disorders including asthma are complex and heterogeneous diseases that affect up to 30% of all children, contributing to a major burden on children, their families, and global healthcare systems. It is now recognized that a dysfunctional airway epithelium plays a central role in the pathogenesis of recurrent wheeze, although the underlying mechanisms are still not fully understood. This prospective birth cohort aims to bridge this knowledge gap by investigating the influence of intrinsic epithelial dysfunction on the risk for developing respiratory disorders and the modulation of this risk by maternal morbidities, in utero exposures, and respiratory exposures in the first year of life. The Airway Epithelium Respiratory Illnesses and Allergy (AERIAL) study is nested within the ORIGINS Project and will monitor 400 infants from birth to five years. The primary outcome of the AERIAL study will be the identification of epithelial endotypes and exposure variables that influence the development of recurrent wheezing, asthma, and allergic sensitisation. Nasal respiratory epithelium at birth to six weeks, one, three, and five years will be analysed by bulk RNA-seq and DNA methylation sequencing. Maternal morbidities and in utero exposures will be identified on maternal history and their effects measured through transcriptomic and epigenetic analyses of the amnion and newborn epithelium. Exposures within the first year of life will be identified based on infant medical history as well as on background and symptomatic nasal s ling for viral PCR and microbiome analysis. Daily temperatures and symptoms recorded in a study-specific Smartphone App will be used to identify symptomatic respiratory illnesses. Ethical approval has been obtained from Ramsey Health Care HREC WA-SA (#1908). Results will be disseminated through open-access peer-reviewed manuscripts, conference presentations, and through different media channels to consumers, ORIGINS families, and the wider community.
Vitamin D supplementation of initially vitamin D-deficient mice diminishes lung inflammation with limited effects on pulmonary epithelial integrity
Publisher: Wiley
Date: 08-2017
DOI: 10.14814/PHY2.13371
Dysregulated Notch Signaling in the Airway Epithelium of Children with Wheeze
Publisher: MDPI AG
Date: 07-12-2021
DOI: 10.3390/JPM11121323
Abstract: The airway epithelium of children with wheeze is characterized by defective repair that contributes to disease pathobiology. Dysregulation of developmental processes controlled by Notch has been identified in chronic asthma. However, its role in airway epithelial cells of young children with wheeze, particularly during repair, is yet to be determined. We hypothesized that Notch is dysregulated in primary airway epithelial cells (pAEC) of children with wheeze contributing to defective repair. This study investigated transcriptional and protein expression and function of Notch in pAEC isolated from children with and without wheeze. Primary AEC of children with and without wheeze were found to express all known Notch receptors and ligands, although pAEC from children with wheeze expressed significantly lower NOTCH2 (10-fold, p = 0.004) and higher JAG1 (3.5-fold, p = 0.002) mRNA levels. These dysregulations were maintained in vitro and cultures from children with wheeze displayed altered kinetics of both NOTCH2 and JAG1 expression during repair. Following Notch signaling inhibition, pAEC from children without wheeze failed to repair (wound closure rate of 76.9 ± 3.2%). Overexpression of NOTCH2 in pAEC from children with wheeze failed to rescue epithelial repair following wounding. This study illustrates the involvement of the Notch pathway in airway epithelial wound repair in health and disease, where its dysregulation may contribute to asthma development.
Differentiation of Marrow Stromal Cells into Photoreceptors in the Rat Eye
Publisher: Society for Neuroscience
Date: 27-08-2003
DOI: 10.1523/JNEUROSCI.23-21-07742.2003
Abstract: Retinal degenerations and dystrophies are the major causes of genetically inherited blindness that are characterized by the apoptotic death of the photoreceptor cell layer of the retina. To date, no treatment exists for these diseases and only recently have they been considered as candidates for gene and stem cell therapies. Here we report the ability of adult CD90 + marrow stromal cells (MSCs) to be induced by activin A, taurine, and EGF into cells (20-32%) expressing photoreceptor-specific markers rhodopsin, opsin, and recoverin in vitro . CD90 + cells were either transduced with recombinant adeno-associated virus expressing green fluorescent protein (GFP) or bromodeoxyuridine (BrdU) labeled and then injected into the subretinal space of adult Royal College of Surgeons rats. Fundus photography and angiography showed no adverse effects of CD90 + MSC transplantation. GFP-expressing cells or BrdU-positive cells covered ∼30% of the entire retinal area. By 2 weeks after injection, CD90 + MSCs integrated into the host retina, forming structures similar to the photoreceptor layer and expressed a photoreceptor-specific marker. No teratoma formation was observed in the recipient retina. The subretinally delivered CD90 + MSCs did not stain for proliferating cell nuclear antigen, indicating that they primarily undergo differentiation rather than proliferation. In addition, we established that transplanted cells can attract synaptic vesicles and hence are potentially capable of signal transduction. This study demonstrates for the first time the partial differentiation of adult CD90 + MSCs into photoreceptors in vitro and in vivo . Our results establish a proof of concept for CD90 + MSC differentiation with autologous transplantation, which may provide a promising therapeutic strategy for the treatment of some forms of genetically inherited retinal degenerations.
Ca-EDTA restores the activity of ceftazidime-avibactam or aztreonam against carbapenemase-producing Klebsiella pneumoniae infections
Publisher: Elsevier BV
Date: 07-2023
Posttransplant bronchiolitis obliterans syndrome is associated with bronchial epithelial to mesenchymal transition
Publisher: Elsevier BV
Date: 04-2009
DOI: 10.1111/J.1600-6143.2009.02558.X
Abstract: Bronchiolitis obliterans syndrome (BOS) compromises lung transplant outcomes and is characterised by airway epithelial damage and fibrosis. The process whereby the normal epithelial configuration is replaced by fibroblastic scar tissue is poorly understood, but recent studies have implicated epithelial mesenchymal transition (EMT). The primary aim of this study was to assess the utility of flow cytometry in detecting and quantifying EMT in bronchial epithelial cells. Large airway brushings were obtained at 33 bronchoscopies in 16 BOS-free and 6 BOS grade 1-3 patients at 2-120 months posttransplant. Flow cytometry was used to assess expression of the mesenchymal markers alphaSMA, S100A4 and ED-A FN and HLA-DR. TGF beta 1 and HGF were measured in Bronchoalveolar lavage (BAL). Expression of all three mesenchymal markers was increased in BOS, as was HLA-DR. BAL HGF, but not TGF beta 1 was increased in BOS. Longitudinal investigation of one patient revealed a 100% increase in EMT markers concurrent with a 6-fold increase in BAL TGF beta 1 and the diagnosis of BOS at 17 months posttransplant. Flow cytometric evaluation of bronchial epithelium may provide a novel and rapid means to assess lung allografts at risk of BOS.
Defining the pediatric response to SARS-CoV-2 variants.
Publisher: Frontiers Media SA
Date: 25-05-2023
DOI: 10.3389/FIMMU.2023.1200456
Abstract: The global population has been severely affected by the coronavirus disease 2019 (COVID-19) pandemic, however, with older age identified as a risk factor, children have been underprioritized. This article discusses the factors contributing to the less severe response observed in children following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including, differing viral entry receptor expression and immune responses. It also discusses how emerging and future variants could present a higher risk to children, including those with underlying comorbidities, in developing severe disease. Furthermore, this perspective discusses the differential inflammatory markers between critical and non-critical cases, as well as discussing the types of variants that may be more pathogenic to children. Importantly, this article highlights where more research is urgently required, in order to protect the most vulnerable of our children.
Exacerbation of chronic cigarette-smoke induced lung disease by rhinovirus in mice
Publisher: Elsevier BV
Date: 04-2022
DOI: 10.1016/J.RESP.2022.103846
Abstract: A significant proportion of chronic obstructive pulmonary disease exacerbations are strongly associated with rhinovirus infection (HRV). In this study, we combined long-term cigarette smoke exposure with HRV infection in a mouse model. Our aim was to better understand the effects of HRV infection on such exacerbations, using a realistic method for generating a COPD-like phenotype. After 12-weeks of cigarette smoke exposure, adult female BALB/c mice were infected with HRV-1A and three days later we assessed a range of outcomes including lung volume and function, collected lung tissue for measurement of viral titre, bronchoalveolar lavage for assessment of pulmonary inflammation and levels of key mediators, and fixed lungs for stereological structural analyses. Cigarette smoke exposure alone significantly increased total cells and macrophages, and reduced MIP-2 in bronchoalveolar lavage. HRV-1A infection alone increased neutrophilic inflammation, IP-10 and total protein in lavage and also increased specific airway resistance measured at functional residual capacity. Cigarette smoke and HRV-1A together impacted various lung structural parameters including increasing stereological lung volume. Our results show that long-term cigarette smoke exposure and HRV-1A infection both in idually impact respiratory outcomes and combine to alter aspects of lung structure in a mouse model, thus providing insight into the development of future mechanistic studies and appropriate interventions in human disease.
Pseudomonas aeruginosa Resistance to Bacteriophages and Its Prevention by Strategic Therapeutic Cocktail Formulation
Publisher: MDPI AG
Date: 02-02-2021
DOI: 10.3390/ANTIBIOTICS10020145
Abstract: Antimicrobial resistance poses a significant threat to modern healthcare as it limits treatment options for bacterial infections, particularly impacting those with chronic conditions such as cystic fibrosis (CF). Viscous mucus accumulation in the lungs of in iduals genetically predisposed to CF leads to recurrent bacterial infections, necessitating prolonged antimicrobial chemotherapy. Pseudomonas aeruginosa infections are the predominant driver of CF lung disease, and airway isolates are frequently resistant to multiple antimicrobials. Bacteriophages, or phages, are viruses that specifically infect bacteria and are a promising alternative to antimicrobials for CF P. aeruginosa infections. However, the narrow host range of P. aeruginosa-targeting phages and the rapid evolution of phage resistance could limit the clinical efficacy of phage therapy. A promising approach to overcome these issues is the strategic development of mixtures of phages (cocktails). The aim is to combine phages with broad host ranges and target multiple distinct bacterial receptors to prevent the evolution of phage resistance. However, further research is required to identify and characterize phage resistance mechanisms in CF-derived P. aeruginosa, which differ from their non-CF counterparts. In this review, we consider the mechanisms of P. aeruginosa phage resistance and how these could be overcome by an effective future phage therapy formulation.
SLC6A14 Impacts Cystic Fibrosis Lung Disease Severity via mTOR and Epithelial Repair Modulation
Publisher: Frontiers Media SA
Date: 09-03-2022
DOI: 10.3389/FMOLB.2022.850261
Abstract: Cystic fibrosis (CF), due to pathogenic variants in CFTR gene, is associated with chronic infection/inflammation responsible for airway epithelium alteration and lung function decline. Modifier genes induce phenotype variability between people with CF (pwCF) carrying the same CFTR variants. Among these, the gene encoding for the amino acid transporter SLC6A14 has been associated with lung disease severity and age of primary airway infection by the bacteria Pseudomonas aeruginosa . In this study, we investigated whether the single nucleotide polymorphism (SNP) rs3788766, located within SLC6A14 promoter, is associated with lung disease severity in a large French cohort of pwCF. We also studied the consequences of this SNP on SLC6A14 promoter activity using a luciferase reporter and the role of SLC6A14 in the mechanistic target of rapamycin kinase (mTOR) signaling pathway and airway epithelial repair. We confirm that SLC6A14 rs3788766 SNP is associated with lung disease severity in pwCF ( p = 0.020 n = 3,257, pancreatic insufficient, aged 6–40 years old), with the minor allele G being deleterious. In bronchial epithelial cell lines deficient for CFTR , SLC6A14 promoter activity is reduced in the presence of the rs3788766 G allele. SLC6A14 inhibition with a specific pharmacological blocker reduced 3 H-arginine transport, mTOR phosphorylation, and bronchial epithelial repair rates in wound healing assays. To conclude, our study highlights that SLC6A14 genotype might affect lung disease severity of people with cystic fibrosis via mTOR and epithelial repair mechanism modulation in the lung.
Elucidating the Interaction of CF Airway Epithelial Cells and Rhinovirus: Using the Host-Pathogen Relationship to Identify Future Therapeutic Strategies.
Publisher: Frontiers Media SA
Date: 07-11-2018
Impaired airway epithelial cell responses from children with asthma to rhinoviral infection.
Publisher: Wiley
Date: 07-2016
DOI: 10.1111/CEA.12767
Abstract: The airway epithelium forms an effective immune and physical barrier that is essential for protecting the lung from potentially harmful inhaled stimuli including viruses. Human rhinovirus (HRV) infection is a known trigger of asthma exacerbations, although the mechanism by which this occurs is not fully understood. To explore the relationship between apoptotic, innate immune and inflammatory responses to HRV infection in airway epithelial cells (AECs) obtained from children with asthma and non-asthmatic controls. In addition, to test the hypothesis that aberrant repair of epithelium from asthmatics is further dysregulated by HRV infection. Airway epithelial brushings were obtained from 39 asthmatic and 36 non-asthmatic children. Primary cultures were established and exposed to HRV1b and HRV14. Virus receptor number, virus replication and progeny release were determined. Epithelial cell apoptosis, IFN-β production, inflammatory cytokine release and epithelial wound repair and proliferation were also measured. Virus proliferation and release was greater in airway epithelial cells from asthmatics but this was not related to the number of virus receptors. In epithelial cells from asthmatic children, virus infection d ened apoptosis, reduced IFN-β production and increased inflammatory cytokine production. HRV1b infection also inhibited wound repair capacity of epithelial cells isolated from non-asthmatic children and exaggerated the defective repair response seen in epithelial cells from asthmatics. Addition of IFN-β restored apoptosis, suppressed virus replication and improved repair of airway epithelial cells from asthmatics but did not reduce inflammatory cytokine production. Collectively, HRV infection delays repair and inhibits apoptotic processes in epithelial cells from non-asthmatic and asthmatic children. The delayed repair is further exaggerated in cells from asthmatic children and is only partially reversed by exogenous IFN-β.
Dysregulated repair in asthmatic paediatric airway epithelial cells: The role of plasminogen activator inhibitor-1
Publisher: Wiley
Date: 19-11-2008
DOI: 10.1111/J.1365-2222.2008.03093.X
Abstract: Asthma is associated with structural changes to airways such as extracellular matrix deposition and epithelial damage. Evidence suggests that asthmatic airway epithelial repair is abnormal and that elevated plasminogen activator inhibitor-1 levels observed in asthma may be involved in the epithelial repair process and in excessive matrix accumulation. To assess the ability of asthmatic airway epithelial cells (AECs) to repair mechanically induced wounds and to investigate the role that plasminogen activator inhibitor-1 plays in the repair process. AECs were isolated from atopic asthmatic and healthy non-atopic children by bronchial brushing, subcultured and wound repair experiments were performed. Plasminogen activator inhibitor-1 gene expression was assessed using real-time PCR while protein activity was measured in cell lysates as well as plasma. The role of plasminogen activator inhibitor-1 in epithelial proliferation and wound repair was investigated using siRNA. Cells from asthmatic children have a significantly longer repair time in comparison with cells from otherwise healthy donors. Plasminogen activator inhibitor-1 mRNA expression was up-regulated 68-fold in freshly isolated asthmatic cells compared with normal cells, and protein levels were also significantly elevated in the asthmatic cell lysates, but plasma levels were similar in both groups. Plasminogen activator inhibitor-1 cells expression increased in both cohorts during culture. Gene silencing substantially reduced the rate of proliferation in asthmatic and healthy cells. Mechanical wounding of epithelial monolayers induced plasminogen activator inhibitor-1 expression in asthmatic and non-asthmatic cohorts, while gene silencing delayed wound repair of healthy cell, with minimal effect on those from asthmatics. Asthmatic AECs are inherently dysfunctional in their ability to repair wounds plasminogen activator inhibitor-1 mRNA and protein activity are constitutively up-regulated in asthmatic epithelium and play functional roles in both proliferation and repair of healthy cells. In asthmatic cells, elevated plasminogen activator inhibitors-1 levels fail to stimulate epithelial repair.
Genome Sequence of a Lytic Staphylococcus aureus Bacteriophage Isolated from Breast Milk
Publisher: American Society for Microbiology
Date: 15-12-2022
DOI: 10.1128/MRA.00953-22
Abstract: We identified a double-stranded DNA (dsDNA) bacteriophage appearing to belong to Herelleviridae , genus Kayvirus . The bacteriophage, Biyabeda-mokiny 1, was isolated from breast milk using a clinical isolate of Staphylococcus aureus . The genome is 141,091 bp in length and encodes 230 putative coding sequences.
Induction of Epithelial–Mesenchymal Transition in Primary Airway Epithelial Cells from Patients with Asthma by Transforming Growth Factor-β1
Publisher: American Thoracic Society
Date: 15-07-2009
Desferrithiocin is a more potent antineoplastic agent than desferrioxamine
Publisher: Wiley
Date: 03-2002
Reduced transforming growth factor β1 (TGF-β1) in the repair of airway epithelial cells of children with asthma.
Publisher: Wiley
Date: 24-05-2016
DOI: 10.1111/RESP.12810
Abstract: Evidence into the role of TGF-β1 in airway epithelial repair in asthma is still controversial. This study tested the hypothesis that the reduced TGF-β1 levels previously observed in paediatric asthmatic airway epithelial cells directly contribute to the dysregulated repair seen in these cells. Primary airway epithelial cells (pAEC) from children with asthma (n = 16) and non-asthmatic subjects (n = 20) were isolated, and subcultured for investigation of TGF-β1 gene and protein via quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Expression of other associated genes such as integrins αvβ6, αvβ8 and MT1-MMP were also tested. Small interfering RNA (siRNA) was employed to assess the role of TGF-β1 during wound repair. TGF-β1 gene and protein expression were significantly downregulated in asthmatic pAEC over the course of repair, compared with cells from non-asthmatic children. Messenger RNA (mRNA) expression of TGF-β1 was also directly implicated in non-asthmatic and asthmatic pAEC proliferation over their quiescent counterparts. Small interfering RNA-mediated knockdown of TGF-β1 compromised repair in non-asthmatic pAEC and exacerbated the dysregulated repair seen in asthmatic pAEC. Expression of major TGF-β1 activators of epithelial cells, integrin αvβ6 and αvβ8 was also measured and there was no difference in αvβ6 gene expression between the two cohorts. Although integrin αvβ8 gene expression was significantly higher in asthmatic pAEC, the expression of MT1-MMP (MMP14) which facilitates the αvβ8 mediated TGF-β1 activation was significantly downregulated. Our data has highlighted the importance of TGF-β1 in pAEC wound repair in vitro. The significantly lower levels seen in asthmatic pAEC subsequently contributes to the dysregulated repair observed in these cells.
Accumulation mode particles and LPS exposure induce TLR-4 dependent and independent inflammatory responses in the lung
Publisher: Springer Science and Business Media LLC
Date: 22-01-2018
The contribution of geogenic particulate matter to lung disease in indigenous children
Publisher: MDPI AG
Date: 24-07-2019
Abstract: Indigenous children have much higher rates of ear and lung disease than non-Indigenous children, which may be related to exposure to high levels of geogenic (earth-derived) particulate matter (PM). The aim of this study was to assess the relationship between dust levels and health in Indigenous children in Western Australia (W.A.). Data were from a population-based s le of 1077 Indigenous children living in 66 remote communities of W.A. ( ,000,000 km2), with information on health outcomes derived from carer reports and hospitalisation records. Associations between dust levels and health outcomes were assessed by multivariate logistic regression in a multi-level framework. We assessed the effect of exposure to community s led PM on epithelial cell (NuLi-1) responses to non-typeable Haemophilus influenzae (NTHi) in vitro. High dust levels were associated with increased odds of hospitalisation for upper (OR 1.77 95% CI [1.02–3.06]) and lower (OR 1.99 95% CI [1.08–3.68]) respiratory tract infections and ear disease (OR 3.06 95% CI [1.20–7.80]). Exposure to PM enhanced NTHi adhesion and invasion of epithelial cells and impaired IL-8 production. Exposure to geogenic PM may be contributing to the poor respiratory health of disadvantaged communities in arid environments where geogenic PM levels are high.
Human Primary Epithelial Cell Models: Promising Tools in the Era of Cystic Fibrosis Personalized Medicine
Publisher: Frontiers Media SA
Date: 07-12-2018
Interleukin-1 is associated with inflammation and structural lung disease in young children with cystic fibrosis
Publisher: Elsevier BV
Date: 11-2018
DOI: 10.1016/J.JCF.2018.05.006
Abstract: Little is known about the role of interleukin (IL)-1 in the pathogenesis of cystic fibrosis (CF) lung disease. This study investigated the relationship between IL-1 signalling, neutrophilic inflammation and structural lung changes in children with CF. Bronchoalveolar lavage fluid (BALf) from 102 children with CF were used to determine IL-1α, IL-1β, IL-8 levels and neutrophil elastase (NE) activity, which were then correlated to structural lung changes observed on chest computed tomography (CT) scans. IL-1α and IL-1β were detectable in BAL in absence of infection, increased in the presence of bacterial infection and correlated with IL-8 (p < 0.0001), neutrophils (p < 0.0001) and NE activity (p < 0.01 and p < 0.001). IL-1α had the strongest association with structural lung disease (p < 0.01) in the absence of infection (uninfected: p < 0.01 vs. infected: p = 0.122). Our data associates IL-1α with early structural lung damage in CF and suggests this pathway as a novel anti-inflammatory target.
Route of exposure alters inflammation and lung function responses to diesel exhaust
Publisher: Informa UK Limited
Date: 27-05-2014
DOI: 10.3109/08958378.2014.909910
Abstract: Mice are commonly used in studies investigating the effects of diesel exhaust exposure on respiratory health. A plethora of studies in this field has resulted in a range of exposure protocols, from inhalation of diesel exhaust, to the administration (via various routes) of diesel exhaust particles in solution. In this study, we compared the physiological consequences of short-term exposure to diesel exhaust via inhalation to those due to exposure to the same diesel exhaust particles suspended in solution and delivered intranasally. Adult BALB/c mice were exposed to diesel exhaust via inhalation for 2 hours per day for 8 days. A representative, simultaneous s le of particles was collected and a second group of mice then exposed to them suspended in saline. A low and a high-dose were studied, with these matched based on respiratory parameters. Six and twenty-four hours after the last exposure we measured bronchoalveolar inflammation, lung volume, lung function and the amount of elemental carbon in alveolar macrophages. Exposure via either route elicited pulmonary inflammation and changes in lung function. We identified significant differences in response between the two routes of exposure, with mice exposed via inhalation generally displaying more realistic dose-response relationships. Mice exposed via intranasal instillation responded more variably, with little influence of dose. Our results suggest that selection of the route of exposure is of critical importance in studies such as this. Further, inhalation exposure, while more methodologically difficult, resulted in responses more akin to those seen in humans.
Changes in airway inflammation with pseudomonas eradication in early cystic fibrosis
Publisher: Elsevier BV
Date: 11-2021
DOI: 10.1016/J.JCF.2020.12.015
Abstract: Neutrophil elastase is a significant risk factor for structural lung disease in cystic fibrosis, and Pseudomonas aeruginosa airway infection is linked with neutrophilic inflammation and substantial respiratory morbidity. We aimed to evaluate how neutrophil elastase (NE) activity changes after P. aeruginosa eradication and influences early disease outcomes. We assessed participants in the AREST CF cohort between 2000 and 2018 who had P. aeruginosa cultured from their routine annual bronchoalveolar lavage (BAL) fluid and who underwent eradication treatment and a post eradication BAL. Factors associated with persistent P. aeruginosa infection, persistent neutrophilic inflammation following eradication and worse structural lung disease one year post-eradication were evaluated. Eighty-eight episodes (3 months to 6 years old) of P. aeruginosa infection were studied. Eradication was successful in 84.1% of episodes. Median activity of NE was significantly reduced post-eradication from 9.15 to 3.4 nM (p = 0.008) but persisted in 33 subjects. High post-eradication NE levels were associated with an increased risk for P. aeruginosa infection in the next annual visit (odds ratio=1.7, 95% confidence interval 1.1-2.7, p = 0.014). Post-eradication NE levels (difference, 0.8 95% confidence interval, 0.1-1.5) and baseline bronchiectasis computed tomography (CT) score (difference, 0.4 95% confidence interval, 0.1-0.8) were the best predictors of bronchiectasis progression within 1 year (backward stepwise linear regression model, R In children with CF, NE activity may persist following successful P. aeruginosa eradication and is significantly associated with bronchiectasis progression. Evaluating strategies to diminish neutrophilic inflammation is essential for improving long-term outcomes.
Bronchial brushings for investigating airway inflammation and remodelling.
Publisher: Wiley
Date: 28-06-2011
DOI: 10.1111/J.1440-1843.2011.02001.X
Abstract: Asthma is the commonest medical cause for hospital admission for children in Australia, affects more than 300 million people worldwide, and is incurable, severe in large number and refractory to treatment in many. However, there have been no new significant treatments despite intense research and billions of dollars. The advancement in our understanding in this disease has been limited due to its heterogeneity, genetic complexity and has severely been h ered particularly in children by the difficulty in obtaining relevant target organ tissue. This review attempts to provide an overview of the currently used and recently developed/adapted techniques used to obtain lung tissue with specific reference to the airway epithelium.
Effect of human rhinovirus infection on airway epithelium tight junction protein disassembly and transepithelial permeability.
Publisher: Informa UK Limited
Date: 08-08-2016
DOI: 10.1080/01902148.2016.1235237
Abstract: No studies have assessed the effects of human rhinovirus (HRV) infection on epithelial tight junctions (TJs) and resultant barrier function. To correlate viral infection with TJ disassembly, epithelial barrier integrity, and function. Human airway epithelial cells were infected with HRV minor serotype 1B (HRV-1B) at various 50% tissue culture infectivity doses (TCID HRV-1B infection affected viability that was both time and TCID HRV-1B infection directly alters human airway epithelial TJ expression leading to increased epithelial permeability potentially via an antiviral response of IL-15.
Assessing the unified airway hypothesis in children via transcriptional profiling of the airway epithelium
Publisher: Elsevier BV
Date: 06-2020
Primary Nasal Epithelial Cells as a Surrogate Cell Culture Model for Type-II Alveolar Cells to Study ABCA-3 Deficiency
Publisher: Frontiers Media SA
Date: 21-02-2022
Abstract: ATP Binding Cassette Subfamily A Member 3 (ABCA-3) is a lipid transporter protein highly expressed in type-II alveolar (AT-II) cells. Mutations in ABCA3 can result in severe respiratory disease in infants and children. To study ABCA-3 deficiency in vitro , primary AT-II cells would be the cell culture of choice although s le accessibility is limited. Our aim was to investigate the suitability of primary nasal epithelial cells, as a surrogate culture model for AT-II cells, to study ABCA-3 deficiency. Expression of ABCA3 , and surfactant protein genes, SFTPB and SFTPC , was detected in primary nasal epithelial cells but at a significantly lower level than in AT-II cells. ABCA-3, SP-B, and SP-C were detected by immunofluorescence microscopy in primary nasal epithelial cells. However, SP-B and SP-C were undetectable in primary nasal epithelial cells using western blotting. Structurally imperfect lamellar bodies were observed in primary nasal epithelial cells using transmission electron microscopy. Functional assessment of the ABCA-3 protein demonstrated that higher concentrations of doxorubicin reduced cell viability in ABCA-3 deficient nasal epithelial cells compared to controls in an assay-dependent manner. Our results indicate that there may be a role for primary nasal epithelial cell cultures to model ABCA-3 deficiency in vitro , although additional cell culture models that more effectively recapitulate the AT-II phenotype may be required.
Intrauterine growth restriction predisposes to airway inflammation without disruption of epithelial integrity in postnatal male mice
Publisher: Cambridge University Press (CUP)
Date: 17-08-2021
DOI: 10.1017/S2040174420000744
Abstract: Evidence from animal models demonstrate that intrauterine growth restriction (IUGR) alters airway structure and function which may affect susceptibility to disease. Airway inflammation and dysregulated epithelial barrier properties are features of asthma which have not been examined in the context of IUGR. This study used a maternal hypoxia-induced IUGR mouse model to assess lung-specific and systemic inflammation and airway epithelial tight junctions (TJs) protein expression. Pregnant BALB/c mice were housed under hypoxic conditions (10.5% O 2 ) from gestational day (GD) 11 to 17.5 (IUGR group term, GD 21). Following hypoxic exposure, mice were returned to a normoxic environment (21% O 2 ). A Control group was housed under normoxic conditions throughout pregnancy. Offspring weights were recorded at 2 and 8 weeks of age and euthanized for bronchoalveolar lavage (BAL) and peritoneal cavity fluid collection for inflammatory cells counts. From a separate group of mice, right lungs were collected for Western blotting of TJs proteins. IUGR offspring had greater inflammatory cells in the BAL fluid but not in peritoneal fluid compared with Controls. At 8 weeks of age, interleukin (IL)-2, IL-13, and eotaxin concentrations were higher in male IUGR compared with male Control offspring but not in females. IUGR had no effect on TJs protein expression. Maternal hypoxia-induced IUGR increases inflammatory cells in the BAL fluid of IUGR offspring with no difference in TJs protein expression. Increased cytokine release, specific to the lungs of IUGR male offspring, indicates that both IUGR and sex can influence susceptibility to airway disease.
Intrinsic biochemical and functional differences in bronchial epithelial cells of children with asthma
Publisher: American Thoracic Society
Date: 15-11-2006
Alpha-1 Antitrypsin Mitigates the Inhibition of Airway Epithelial Cell Repair by Neutrophil Elastase.
Publisher: American Thoracic Society
Date: 03-2016
Related Organisations
Department Of Agriculture And Food Western Australia
Location: Australia
Related Funding Activities
Discovery Projects - Grant ID: DP110101706
Start Date: 2011
End Date: 12-2013
Amount: $550,000.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP170104346
Start Date: 02-2017
End Date: 12-2020
Amount: $401,000.00
Funder: Australian Research Council
View Funded Activity